System Upgrade

Kiryu Yume rolled over and was about to put down his phone when something suddenly trembled deep within his consciousness.

A numb sensation shot up from the base of his spine, climbing vertebra by vertebra. He opened his eyes and stared at the ceiling as the panel in his mind appeared on its own.

[System upgrade complete]

[Current version: 2.0]

[New feature: Bond Upgrade System]

Words emerged one by one across the panel, edged in a faint golden glow.

[Bond Upgrade Details]

[Each bond target can be upgraded. Upgrade requirement: Personally say "Mom" a total of 30 times. Each target can only be counted once per day. Current count: 0]

[Notice: Due to a missing counter module in System Version 1.0 (Bug #0001), previous instances of calling someone Mom were not recorded. This has now been fixed.]

Kiryu Yume sat up in bed and stared at the words "Current count: 0."

He had called Kamuro Masumi that more than once. He had no idea how many times he had called Sakayanagi Arisu that. He had called Morishita Ran twice today. None of it counted.

He had barely exhaled before he could curse when another message popped up.

[Bug compensation being issued]

[Compensation: Luck +1]

[Compensation details: This bug caused the host to remain in a long-term "effort expended without reward" state. Following system evaluation, attribute compensation has been granted.]

There was compensation? Then it was fine!

Luck plus one. He had never seen that stat before. It was probably a hidden bonus exclusive to compensation. Staring at the tiny green light on the air conditioner above him, the corner of his mouth slowly lifted.

The system was finally starting to repay what it owed him, with an unexpected bonus thrown in.

He pictured Morishita Ran confidently pulling her twin braids taut, only to somehow miss her shot, and laughed.

[Affinity check]

[Kamuro Masumi: Affinity requirement met]

[Sakayanagi Arisu: Affinity requirement met]

[Morishita Ran: Affinity requirement met]

[The above targets meet the prerequisite for upgrading. Accumulate 30 personal utterances of "Mom" to trigger a bond upgrade.]

He closed the panel and lay back down. Before the lingering warmth between his brows had faded, his phone screen suddenly lit up.

Friend request: Horikita Suzune. Note: I got your contact information from Kikyo.

Kiryu Yume accepted the friend request.

The chat window opened, and the "typing..." indicator on the other end flashed for quite a while.

Horikita Suzune: Please return the 200,000 points my brother transferred to you.

Kiryu Yume looked at that message for two seconds. Before he could reply, another one followed.

Horikita Suzune: I'll repay it. Return the 200,000 to my brother first. On the day I receive my monthly points, I'll transfer them to you in installments until it's paid off.

Kiryu Yume leaned against the headboard, read it through, and replied.

Kiryu Yume: You really are a lot like your brother.

Horikita Suzune: What do you mean?

Kiryu Yume: When he transferred the money, he said "Transferred it to you" with a blank face. Now you're saying "Please return it to him, I'll pay in installments" with a blank face. You two were cut from the same mold. Even the way you talk is the same.

Horikita Suzune: Please discuss the matter at hand.

Kiryu Yume: The matter at hand is that you siblings are both tsundere. He's the older model, and you're the smaller one.

The other side went silent for quite a while.

Horikita Suzune: Don't talk nonsense.

Kiryu Yume: Last time, when I said your brother was a tsundere on the open ground, you blushed. Now that I'm calling you one too, your hand must be shaking.

Horikita Suzune read it but did not reply.

Kiryu Yume: See? No reply. You did the same thing last time. Whenever I hit the mark, you stop responding. Standard tsundere behavior.

Horikita Suzune read it.

Still no reply.

Kiryu Yume: You still there?

Read. No reply.

Kiryu Yume: I'm too lazy to look at your installment plan. Keep the interest and buy yourself some reference books. You don't need to worry about the 200,000.

Horikita Suzune read it.

Kiryu Yume: Not replying again. Good night, Tsundere Number Two.

He put his phone on the nightstand. His mind automatically conjured up Horikita Suzune sitting in her dorm room, glaring at the screen with a dark expression, perhaps with a sheet of paper beside her detailing the installment interest. He smiled and closed his eyes.

The next morning, Kiryu Yume left early as usual, based on the meeting time written on the back of Kamuro Masumi's note.

The elevator doors chimed open, and Sakayanagi Arisu stepped out. The rhythm of her cane was much steadier than the last time he had seen her, and the color had returned to her lips by seventy or eighty percent.

Her violet eyes swept over him standing in the lobby, and her lips twitched slightly.

"The kitten isn't ten minutes early today."

"Got here right on time." Kiryu Yume fell in beside her, automatically slowing his pace.

When they passed the vending machines, Sakayanagi Arisu tilted her head for a glance. Before she could speak, Kiryu Yume had already stepped forward.

"I'll get it. Don't move."

He bought two cans of black coffee. He briefly pressed one against the back of Sakayanagi Arisu's hand to test the temperature, then gently placed it in her palm.

Sakayanagi Arisu lowered her head and looked at the patch of skin on the back of her hand that his fingertips had touched. She opened the coffee and took a small sip.

"Did you finish filling out the notebook?"

"I did. I can memorize it all before Friday."

"I'll test you during Saturday's tutoring session. I'll also pick a few questions from the parts we covered before." She walked several steps ahead.

Kiryu Yume turned his head to look at her profile as she walked with her cane, her long silver-white hair lightly swaying in the morning breeze.

"Mom Sakayanagi." He lowered his voice until only the two of them could hear.

Sakayanagi Arisu stopped and turned around. Her violet eyes rested on his face for two seconds. She shifted her cane to her left hand, then extended her right and lightly tapped his forehead with one fingertip.

"The kitten called me before reaching the slope today. Last week, you only called me when we reached it. That means you memorized your notes well enough to have spare room in that head of yours."

She withdrew her hand and gripped her cane again, the curve of her lips slightly more pronounced than before.

"I'm adding three questions to Saturday's test. Since you called me on your own initiative, consider it the examination fee I collected."

Kiryu Yume pressed the spot she had tapped. Her touch still lingered there, faintly cool. He opened his mouth, wanting to ask what kind of examination fee that was, but Sakayanagi Arisu had already turned and continued ahead.

Her cane tapped against the concrete path, her steps far steadier than before.

The system panel flickered.

[Sakayanagi Arisu: 1/30]

At the foot of the slope, Sakayanagi Arisu stopped. As always, she adjusted her breathing in advance. Kiryu Yume waited beside her until she had finished before speaking.

"I filled out the blank line on the back of the note. My handwriting isn't as nice as yours. When are you checking it?"

Sakayanagi Arisu turned her face toward him.

"At Saturday's tutoring session. Write that blank line from memory in front of me."

She turned back toward the slope and took a step forward with her cane.

Kiryu Yume stood at the bottom and watched her small figure make her way upward. Her stride had returned to normal, and even the rhythm of her silver-white hair was noticeably lighter than before.

He looked down at the dark blue twin braid on his left wrist and headed toward the school building.

During lunch break, Kamuro Masumi was replenishing her coffee at the vending machine at the end of the hallway.

Kiryu Yume had gone to buy water, and the two of them ran into each other in front of the machine.

Kamuro Masumi was pressing buttons on the screen. Seeing him beside her, she paused for half a beat. Her long straight purple hair hung loose behind her shoulders, and her expression was as indifferent as usual. She only glanced at him, treating that as a greeting.

Kiryu Yume waited until she finished buying her drink before stepping up to select his water.

Kamuro Masumi stood beside him, opened her can of coffee, and took a sip. Then she took a folded note from her pocket and handed it to him with a brisk motion.

"From Sakayanagi. She asked me to give this to you for Saturday's tutoring session. Look it over beforehand."

Kiryu Yume accepted the note and unfolded it. It contained several short-answer outlines handwritten by Sakayanagi Arisu, the writing much neater than on the previous note.

He folded it back up and slipped it into his pocket, then looked at Kamuro Masumi.

"Mom Kamuro."

Kamuro Masumi's hand paused as she drank her coffee, and she lowered the can.

"You're getting more and more used to saying it."

Her tone was as cold as usual, but unlike before, she did not say, "I'll kick you if you say that again." Instead, she switched the coffee can to her other hand and pulled another folded note from her pocket.

"Also. These are my notes. The question types are different from Sakayanagi's, so review them yourself. I'll be at Saturday's tutoring session too. By then, you'd better be able to answer my questions as well, not just hers." Her speech noticeably sped up for the last few words.

Kiryu Yume stacked the two notes together and tucked them into his pocket, looking at Kamuro Masumi's slightly averted face.

The tips of her ears were red, but her expression did not change in the slightest.

"Thank you, Mom Kamuro." He put the thank-you before the mom.

Kamuro Masumi raised the coffee can to her lips again and turned toward the other end of the hallway. After three steps, she stopped without looking back.

"Don't be late for Saturday's tutoring session. The day after Sakayanagi stayed up organizing those notes for you last time, her complexion was frighteningly bad. If you're late, she'll say it's fine, but I'll kick you for her." With that, she kept walking, her long straight purple hair lightly swaying behind her shoulders.

The system panel flickered again.

[Kamuro Masumi: 1/30]

Kiryu Yume stood in front of the vending machine, popped open his drink, and took a sip. The coolness was just enough to suppress that number still burning in his mind.

Before school ended that afternoon, Kiryu Yume clipped the two notes side by side inside his notebook.

The twin braid on his left wrist lightly brushed the edge of the notes. Dark blue fibers left an almost imperceptible shadow across the paper. He closed the notebook and put it in his bag just as his phone vibrated in his pocket.

Morishita Ran: Restocking at the convenience store. Wait downstairs.

Kiryu Yume picked up his bag and left the classroom.

Morishita Ran stood beside the vending machine in the first-floor lobby, an unopened lollipop between her lips. When she saw him, she took it out of her mouth, her blue-violet drooping eyes sweeping over him.

"You're about forty seconds slower than usual today. What were you dawdling over in class?"

"Organizing notes."

Morishita Ran shifted the lollipop from one corner of her mouth to the other. When they reached the convenience store entrance, she suddenly stopped and turned around. Less than half a step separated them.

The automatic doors beside them opened and closed, then closed and opened again. The wind blew her short dark blue hair over half her face.

Kiryu Yume reached out and tucked those strands behind her ear. He had done it several times already, but her ear still turned red.

"Mom," he said.

The curve at the corner of Morishita Ran's lips finally lifted. She bit down on her lollipop with a crisp crunch.

"Your voice was louder than yesterday." She took a soda-flavored lollipop from her pocket, unwrapped it, and held it to his lips. The candy lightly touched his lower lip and stayed there.

Kiryu Yume opened his mouth and took it. The soda flavor burst across his tongue.

"This one gets deducted from your inventory. Pay me back after we finish restocking." She turned and pushed open the convenience store door.

The system panel flickered.

[Morishita Ran: 1/30]

Kiryu Yume followed behind her with the lollipop in his mouth. All three of their counts had become one today.

Between the shelves, Morishita Ran stood on tiptoe and reached for the top row of soda-flavored lollipops. Kiryu Yume reached over her from behind, took down the entire box, and handed it to her.

Morishita Ran accepted the box and looked up at him. "You don't need to help next time. I can reach it myself."

"Your foot shook when you stood on tiptoe."

"The floor was slippery." Hugging the box to her chest, she turned toward the checkout counter. The tips of her ears reddened another shade beneath the convenience store's white lights.

Kiryu Yume took the lollipop from his pocket and set it on the counter beside her box. Morishita Ran glanced at the candy, then at him.

"The one I just gave you doesn't count as repayment yet."

"I'll leave this one with you and repay it tomorrow."

"How are we calculating interest?"

"One soda-flavored one becomes two tomorrow." Kiryu Yume tapped his student ID against the payment terminal.

Morishita Ran narrowed her blue-violet eyes. "Loan shark. But your aim isn't reliable enough for me to gamble on interest with you. One for one, interest-free."

She opened the box, took out two soda-flavored lollipops, and stuffed them into his uniform pocket. Then she hugged the rest and headed for the door. At the entrance, she tilted her head and looked back at him.

"Same thing tomorrow. Don't be late."

Kiryu Yume put his hand in his pocket, his fingertips touching the two newly added lollipops. "If I'm late, the back of your neck gets flicked one more time. I won't tell you which one it is."

She pushed open the door and went outside. The tips of her short dark blue hair swayed once in the gap before the automatic doors closed, then disappeared.

Kiryu Yume stood beside the register, shifted the soda-flavored lollipop in his mouth to the other corner, and followed her out.