Chapter Summaries

Su Yang and the five sisters shared omurice, and Nino tried to suppress her growing appreciation for him. When Su Yang brought out fifth-grade textbooks to begin tutoring them, the sisters felt insulted.

• Nino and Su Yang each enjoyed the other's omurice but concealed their thoughts.
• Nino restrained her rising fondness for Su Yang because she feared betraying her sisters, especially May.
• Ichika said she liked Su Yang's omurice, while May ate hers from a plate.
• Su Yang brought out fifth-grade textbooks as study materials, shocking the sisters.
• May and Nino challenged Su Yang over treating their academic level as elementary-school level.

Su Yang challenged the five sisters to prove their elementary-school math skills with a test. After he astonishingly calculated an enormous multiplication problem in his head, they set to work on their papers.

• Nino claimed she had earned perfect scores in elementary school, then hesitated when Su Yang asked which grade.
• Su Yang sat the five sisters down and challenged them to score full marks on an elementary-school test.
• Su Yang asked Yotsuba to bring out a copier, and test papers appeared before the sisters.
• May objected to the difficult calculations and asked to use a calculator, but Su Yang refused.
• Miku challenged Su Yang to calculate an enormous multiplication problem without a calculator, and he answered instantly.
• May checked his answer on her phone, and the sisters returned to their papers after seeing it was correct.

Su Yang tested the five sisters, found their elementary-school math skills far below expectations, and gave them fourth-grade textbooks to study. After they began to understand the material, he started class and insisted that they drink unsweetened soy milk for better concentration.

• Su Yang watched Nino, Ichika, May, Yotsuba, and Miku work through questions and saw that they struggled badly.
• Su Yang graded the sisters' papers, giving them scores of 22, 17, 33, 22, and 10 points.
• Su Yang handed the sisters fourth-grade textbooks and explained that he had prepared elementary-level work to help them regain confidence.
• The sisters read their textbooks for an hour and found the material easier to understand than the initial test had suggested.
• Su Yang began class and told May that he had left sugar out of the soy milk because it could affect their concentration.

Su Yang taught the Quintuplets mathematics by deriving it from the basics, and they followed his explanations through a full day of study. The lesson ended at dusk, when Ichika discovered she had missed repeated calls and rushed to call back, prompting Su Yang to wonder who had been trying to reach her.

• Su Yang told the Quintuplets to prepare notes and asked Nino to find a notebook with at least 200 pages for his mathematics lesson.
• Su Yang began deriving mathematics from 1+1=2, and the sisters found that they could understand and keep up with him.
• Yotsuba realized that studying could be manageable when she understood how the ideas connected.
• Su Yang finished reviewing mathematics from middle school through the end of the second year of high school, and the sisters noticed it was already dusk.
• Su Yang told Ichika that her phone had been ringing throughout the lesson, and she hurried to call back from the balcony.
• Su Yang wondered whether Ichika had someone important in her life, such as a boyfriend.

Su Yang’s lesson helped the quintuplets solve problems they had once found impossible, and he revealed that he had helped write their math textbook under the pen name Tianchao Su. The sisters recognized his name in the book, leaving them stunned by his connection to their studies.

• Su Yang explained that he would need to schedule lessons around Ichika’s work, and Miku clarified that Ichika did not have a boyfriend.
• Nino and May tried their old fifth-grade test papers and discovered they could now solve the problems without a calculator.
• Yotsuba tackled her high-school textbook exercises and found that she could solve them, possibly even earning a perfect score.
• Su Yang ended the lesson after receiving a dinner invitation from his maid and explained that understanding the material made it hard to forget.
• Su Yang told Miku that he wrote textbooks under the pen name Tianchao Su, and Yotsuba found that name listed among her math book’s editors.

After the quintuplets discovered that Su Yang had written their elementary school textbooks, Miku accompanied him downstairs and admitted she wanted his next lesson to cover the Warring States period. Su Yang reassured her that her interest in famous generals was nothing to be ashamed of.

• Nino and the other sisters were stunned when Su Yang confirmed he had written the textbooks, and Ichika learned what had happened after returning from a phone call.
• Su Yang left the apartment, and Miku went with him to buy May some red bean buns.
• In the elevator, Miku told Su Yang that Nino had said he could have stayed for dinner, and he explained that his maid was waiting for him at home.
• Su Yang guessed that Miku wanted the next lesson to cover the Warring States period and asked why she had been keeping her interest in famous generals secret.
• Miku explained that she had grown interested in the period after playing a game Yotsuba lent her, and Su Yang told her he liked famous generals too.

Su Yang arranged an early history lesson with Miku before the sisters' fireworks festival, and Miku promised to wear white stockings for him. Back at the apartment, Ichika, Nino, and Yotsuba suggested that May get back together with Su Yang, shocking May.

• Miku told Su Yang that the sisters planned to watch the fireworks festival the next day and asked him to come early.
• Su Yang agreed to start the lesson at seven, and Miku said she would wear white stockings for him.
• Ichika, Nino, and Yotsuba said they could accept May getting back together with Su Yang.
• May objected that her sisters had previously urged her to break up with Su Yang after learning she was his backup.

The quintuplets discussed whether May still had feelings for Su Yang, while Ichika reflected on Miku’s closeness to him and the new polygamy system. Su Yang continued tutoring the sisters, then waited for Nino and met a mysterious girl in a yukata.

• Nino argued that May still had a chance with Su Yang because he was single, while May insisted she no longer had feelings for him.
• Yotsuba and Ichika offered to help May make amends, and Ichika privately wondered whether Miku and Su Yang might end up together under the polygamy system.
• The next morning, Miku got all five sisters up at seven, and Su Yang continued teaching them.
• After the lesson, Nino asked Su Yang to wait, and about ten minutes later he turned to find a young girl in a red-pigeon-patterned yukata behind him.

Su Yang tried to identify the Nakano sister standing before him in a red plaid yukata. He ruled out Ichika because of her pierced ears, while the girl continued testing whether he could recognize her.

• Su Yang failed to recognize the girl, whose hairstyle and outfit could not distinguish her from her sisters.
• Su Yang ruled out Ichika because she had pierced ears and her sisters did not.
• Ichika felt relieved that Su Yang’s explanation showed they had done nothing suspicious.
• The girl asked Su Yang whether he thought she was Nino.

At the fireworks festival, Su Yang recognized May despite her attempt to pose as Yotsuba, while Ichika wondered why he had not used her as a shield from girls approaching him. Su Yang guessed that Ichika worked as a minor actress and hoped to become a famous idol or actress, leaving her stunned and asking how he had figured it out.

• Su Yang told Nino that he knew the girl before him was not Nino, and Nino admitted she no longer hated him as much.
• May asked whether Su Yang thought she was May, but he insisted she was and whispered something that made her blush.
• May hurried everyone toward the festival snacks and fireworks, and the five sisters came down together in yukata.
• Ichika returned from her phone call and noticed Su Yang refusing attention from girls while keeping his distance from her.
• Ichika asked why Su Yang had not used her as a shield, and he explained that it might cause trouble because he suspected she worked as a minor actress.
• Su Yang guessed Ichika wanted to become a famous idol or film actress, and she asked how he had reached that conclusion.

Su Yang learned that Ichika was secretly pursuing acting and promised to keep it from her sisters. At the fireworks festival, he joined the five sisters and stayed with Ichika while the others went to buy snacks.

• Su Yang revealed that he had overheard Ichika discussing an audition and learned she hoped to become an idol like Sakurajima Mai.
• Ichika asked Su Yang to keep her acting career secret, and he wished her luck with the audition.
• Ichika offered to help Su Yang, but he held her wrist and kissed her before the five sisters appeared in matching yukata.
• The sisters invited Su Yang to the fireworks festival and split up to buy their preferred snacks, leaving Ichika with him.
• Ichika asked why Su Yang had not complimented them, and he said she was already admired by the men around them.

Su Yang explained that he had tricked May into thinking he knew which sister she was, then used Ichika as a fake girlfriend to fend off girls who wanted to approach him. He claimed their apparent kiss was only a camera angle, but Ichika finally asked whether he had actually kissed her.

• Su Yang reasoned that Ichika and her sisters wanted May to get back together with him, but said he wanted to focus on studying.
• Ichika asked what Su Yang had told May, and he admitted he had guessed May's identity after seeing her sisters upstairs.
• Ichika received a phone call and stepped away to answer it while Su Yang stayed behind.
• Su Yang pretended to be Ichika's boyfriend to drive away the girls who wanted to invite him out.
• Su Yang claimed he and Ichika had not touched, though he had actually kissed her while she was stunned.
• Ichika recovered from her daze and asked Su Yang whether he had just kissed her.

After Su Yang denied kissing Ichika, she told him about an audition for a production supposedly involving Sakurajima Mai. Su Yang revealed the production was a scam, and the chapter ended with Ichika learning that Mai attended their school as Su Yang’s senior.

• Su Yang denied that he had kissed Ichika, and she reluctantly agreed to pretend it had not happened.
• Ichika told Su Yang that the role she planned to audition for included a kissing scene and was said to involve Sakurajima Mai.
• Su Yang made a brief call, then warned Ichika that the production was a scam and gave her Mai’s manager’s work number.
• Ichika called her agency and passed along Su Yang’s warning and the manager’s contact information.
• Su Yang told Ichika that Sakurajima Mai attended their school and was his senior.

May, Su Yang, and Ichika met after May bought takoyaki and festival snacks, and Su Yang suggested that he and May look around together. Ichika agreed to watch their things, but the chapter ended when two unexpected people appeared and offered to eat the food.

• May returned with takoyaki and a bag of festival snacks after finishing the yakisoba she had bought.
• May realized Ichika was distracted because she had missed the chance to attend school with Sakurajima Mai, her idol.
• May offered Su Yang a takoyaki ball, and Ichika teased them about how close they were.
• Su Yang invited May to look around with him and left Ichika to watch their belongings.
• Two people appeared and offered to eat the snacks, surprising Ichika.

Ichika, Nino, and Yotsuba followed May and Su Yang through Central Park, while Ichika struggled to hide the truth about her staged kiss with Su Yang. Su Yang led May to a bench on the park’s outskirts, leaving the sisters to follow them.

• Nino and Yotsuba revealed that they had followed May, hoping she and Su Yang would reconcile, and Ichika asked where Miku was.
• Yotsuba explained that Miku was absorbed in a shop selling warlord face masks.
• May pulled Su Yang away from girls who were flirting with him and questioned him about a kiss, prompting Nino and Yotsuba to ask Ichika what had happened.
• Ichika claimed that she and Su Yang had only pretended to kiss, then redirected her sisters’ attention when she saw May and Su Yang move toward the outskirts.
• Su Yang led May to a bench in a well-lit section of the park, and the three sisters followed them.

Su Yang treated May’s sprained foot, while Ichika, Nino, and Yotsuba secretly watched them and misunderstood their interaction. Later, the group reunited and followed Nino to the restaurant rooftop she had reserved to watch the fireworks.

• Su Yang had May sit down, checked her sprained foot, and offered to massage it in exchange for her help.
• Ichika, Nino, and Yotsuba hid in the bushes and watched Su Yang and May, then retreated after realizing their interaction seemed intimate.
• At the gathering spot, Miku offered May fried noodles, but May said she could not eat.
• Nino led everyone toward the restaurant rooftop she had reserved for the fireworks, while Su Yang walked beside her and talked with her.

Ichika questioned May about reconciling with Su Yang, while Nino struggled with what she had witnessed in the park. Su Yang left the sisters to watch the fireworks and got into a black sedan, where the driver challenged him about saying he had been busy lately.

• Ichika asked May whether she planned to get back together with Su Yang, and May said they were not suited and he had not considered her feelings.
• Ichika remained confused about May’s choices and her own relationship.
• Su Yang noticed Nino’s silence, admitted he knew she, Ichika, and Yotsuba had watched him and May in the park, and asked them to keep it secret.
• Yotsuba pointed out that the fireworks had begun, and Su Yang parted from the five sisters so they could watch together.
• At 8:44 p.m., Su Yang got into a black sedan, and the driver asked whether he had not said he was busy lately.

Su Yang considered what would happen if he reconciled with May and how he should treat her four sisters. The next day, the five sisters finally arrived at school, where Ichika introduced herself to Class 2-C.

• Su Yang rejected Miss Yayoi’s advances and thought about reconciling with May and asking all five sisters to stay single.
• Hayasaka Ai praised Su Yang’s mood, and he said the sisters’ performance would decide what happened next.
• Su Yang arrived at class and found the five sisters’ seats empty as Suou Amane teased him about skipping school.
• The five sisters hurried into the classroom, and Ichika told a classmate that she was a student in Class 2-C.

Su Yang and the others welcomed several absent students back to class and reviewed their efforts to address truancy. The investigation into Tokisaki Kurumi’s disappearance remained unresolved, with no evidence of how she vanished or why.

• Ichika and Nino introduced themselves, and the Nakano sisters quickly joined the class groups.
• Su Yang and Suou Amane discussed how the five Nakano sisters were identical quintuplets.
• Su Yang noticed Yukino Yukinoshita watching cat videos and an unfamiliar girl he suspected was Ayanokoji Kiyotaka.
• Yukino told Su Yang that both students she and Ichinose Honami had approached had returned to school.
• Shinomiya reported that Ayanokoji Kiyotaka had signed a promise not to skip class and had returned.
• Shinomiya said Tokisaki Kurumi had vanished without appearing on nearby surveillance, and her family had received no ransom demands.

Su Yang praised the students who had helped Uzaki-chan return to school, then addressed Shuchiin Academy at the morning assembly. After school, the Nakano sisters resisted studying for their midterms, and Yotsuba asked Su Yang whether he had noticed anything unusual.

• Su Yang heard that Uzaki-chan had stopped attending school out of guilt because she passed Shuchiin Academy while her friend failed, and because she felt self-conscious about her appearance.
• Su Yang gave a speech as Student Council President at the morning assembly, leaving the five sisters surprised by his composed demeanor.
• Su Yang reminded the Nakano sisters that their midterm exams were less than three days away and that they still had three subjects to study.
• Nino and May argued that passing grades, or perfect scores in math and history, would be enough, while the sisters showed little interest in continuing their study session.
• Yotsuba asked Su Yang whether he had noticed anything particularly unusual.