Amae Koromo

Biodata

Feature	Information
Name	Amae Koromo (天江衣)
Alias(es)	“Child Loved by the Tiles”; “Full Moon Koromo”; “Mahjong Demon King”; “Great Demon King” 2 27
Gender	Female
Age	16
Birthday	September 6
Zodiac	Virgo
Height	127 cm
Affiliation	Ryumonbuchi High School; Ryumonbuchi High School Mahjong Club
Occupation/Role	Second-year student; ace of the Ryumonbuchi mahjong club; national-level mahjong player 2
First Appearance	Chapter 2

Background / History

Koromo’s parents died in an accident after declining an opportunity to work abroad in order to spend more time with her. She internalized guilt over their deaths and became profoundly lonely, often speaking to animals or insects instead of people. 16

She lives separately in an isolated villa on the Ryumonbuchi estate. Although she is technically free to leave, Ryumonbuchi Toka explains that Koromo was kept apart because Toka’s father feared that getting close to her would bring misfortune. Koromo is especially severe and dangerous during full moons. 3 14

Before the main story, Koromo helped establish Ryumonbuchi High as a major force. The school reached the National Tournament as Nagano’s first-place representative, and Koromo became known nationally as one of the three “children loved by the tiles.” 2 10

Her initial meeting with Kageyama Sora gives her a rare opponent who treats her extraordinary mahjong as something fascinating rather than frightening. Their bond gradually draws her out of isolation, while her tournament encounters lead her to consider friendship with other players. 2 3 56

Appearance

Koromo is an exceptionally petite girl with long golden hair and a childlike appearance despite being a second-year high school student. Her outwardly sweet, doll-like presentation sharply contrasts with the oppressive presence she displays at the mahjong table. 2 10 43

• Stands 127 cm tall. 2
• Wears a signature oversized red rabbit-ear hair accessory. 2 26
• Frequently wears pink dresses, pink-themed uniforms, or a pink Lolita-style pinafore. 26 43 142
• Her eyes are described as turning crimson when her intimidating mahjong persona surfaces. 49

Personality

Koromo presents herself as cute, affectionate, and playful around people she trusts, particularly Sora. She enjoys being doted on, becomes openly needy when she feels ignored, and is frightened by horror films despite her fearsome reputation. 15 43 145

Beneath that sweetness, she is perceptive, sharp-tongued, and capable of calculated cruelty. In mahjong, she relishes overwhelming opponents and making them fear her, using a harmless appearance to conceal a ruthless competitive nature. 26 50 53

Her isolation leaves her deeply afraid of abandonment. She clings to Sora in her sleep, asks others not to leave her, and gradually admits that she feels jealousy and loneliness. 3 43 57 Despite this, she sincerely wants friends: she tries to return Haramura Nodoka’s penguin plushie, later accepts her Ryumonbuchi teammates as friends and family, and shows concern when Kunihiro Hajime might be hurt. 40 56 146

Abilities & Skills

Luck-Based Mahjong and Field Control

Koromo is a luck-based player whose presence controls the flow of a mahjong table. Opponents struggle to form winning hands, call pon or chi, or even advance their hands while she guides the round toward her own victory. 2 49

• Can suppress opponents’ ability to win or make calls. 2
• Manipulates the tile wall and leaves apparent openings to lure opponents into actions that benefit her. 50
• Can restore the tile wall’s arrangement through a pon, negating an opponent’s attempt to disrupt her planned draw. 50
• Her pressure can overwhelm opponents psychologically, leaving them panicked or unable to play effectively. 49 52 53
• Her control is not absolute: Kageyama Sora’s play enables other players to reach tenpai and win against her field, while Yumi Kajiki disrupts one of her planned Under the Sea victories by dealing into Saki Miyanaga. 3 52

Full Moon State

Koromo declares herself “invincible” under a full moon. Her field control is stated never to have failed under those conditions, and her dangerous side becomes especially pronounced during moonlit nights. 2 3 14

• Enhances the suffocating pressure of her mahjong presence. 2 3
• Allows her to force rounds toward the final tile of the wall. 2
• Is associated with the “Full Moon Koromo” reputation feared by other players. 2

Haitei Raoyue / Under the Sea

Koromo’s signature winning method is Haitei Raoyue, referred to in the tournament as Under the Sea: winning by self-drawing the final tile of the wall. 2 50

• Prevents other players from winning before the final draw. 2
• Can be prepared through her control over calls, tile order, and opponents’ decisions. 50
• Wins multiple consecutive Under the Sea hands during the prefectural captain’s match. 50 51
• Her repeated use of the method defies Haramura Nodoka’s statistical analysis. 51

Voice of Demons

After Yumi Kajiki interrupts her planned Under the Sea win, Koromo reveals Voice of Demons as another means of victory. 52

• Lets her continue winning even after her final-tile strategy is disrupted. 52
• Accompanies a far more intense aura that freezes the arena and terrifies her opponents. 52
• Contributes to her taking a 27,000-point lead by the end of the captain’s match first half. 52

Spiritual Sensitivity

Koromo can sense unusual auras and supernatural disturbances around other players. 46 109

• Detects an “interesting aura” around Toyoko Momoko. 46
• Notices that Jindai Komaki’s suppressed aura is returning and growing stronger before her possession is announced. 109

Story Role / Major Arcs

Introduction and Sora’s First Match

Toka introduces Koromo to Sora as a master of luck-based mahjong. Koromo challenges him during a full moon and repeatedly defeats him with Haitei Raoyue, but his admiration and willingness to continue playing leave an impression on her. 2 3

Isolation and Growing Attachment

Sora learns that Koromo lives alone in an isolated villa. While asleep, she begs him not to leave, revealing the fear and dependence beneath her fearsome reputation. 3 She later confides in him about her parents’ deaths and the guilt she carries. 14 16

Prefectural Tournament

Koromo arrives late to the prefectural preliminaries after oversleeping, with Sora taking her to the venue by motorcycle. 27 28 During the General Battle, she reveals the far more frightening side of her mahjong, dominates Saki Miyanaga, Ikeda Kana, and the other competitors, and repeatedly wins with Under the Sea. 48 49 50

When her final-tile strategy is interrupted, Koromo becomes enraged and unveils Voice of Demons, securing a commanding lead. 52 Her overwhelming play continues through the second half, where she deliberately keeps Kazekoshi Girls’ High at zero points. 53

Friendship and Family

After the tournament, Toka reassures Koromo that mahjong can bring her friends. Koromo begins accepting Toka, Inoue Jun, Kunihiro Hajime, and Sawamura Tomoki as people who genuinely care for her. 56 She also seeks friendship with Nodoka, first through the damaged penguin plushie and later through their shared interactions. 40 43

National Tournament and Later Events

Koromo participates in training using Sora’s holographic mahjong system and eagerly challenges simulated high-level opponents alongside Saki. 85 During the national tournament, she senses Jindai Komaki’s abnormal aura before Komaki’s possession becomes public. 109

At a Ryumonbuchi family banquet, Koromo initially refuses to attend because she believes she is unwelcome. After overhearing guests slander her, she is comforted and defended by Sora and Toka; she ultimately presents a mahjong-tile ornament to the family patriarch for his birthday. 164 166 167

Relationships

• Kageyama Sora — Her cousin and romantic partner. His acceptance of her mahjong and his care for her loneliness become central to Koromo’s emotional growth; she is openly affectionate, possessive, and dependent on him. 2 3 43 145
• Ryumonbuchi Toka — Cousin, teammate, protector, and close friend. Toka defends Koromo from family isolation and encourages her to find people who can enjoy mahjong with her. 3 11 56
• Kunihiro Hajime — Ryumonbuchi teammate and friend. Koromo worries about Hajime’s feelings and proposes that they remain close rather than allow jealousy to divide them. 43 146 147
• Inoue Jun — Ryumonbuchi teammate who teases Koromo but treats her as a cherished younger-sister figure. 56 109
• Sawamura Tomoki — Ryumonbuchi teammate who joins Jun and Toka in affirming that Koromo already has friends. 56
• Haramura Nodoka — A formidable rival whom Koromo hopes to befriend. Koromo tries to return Nodoka’s penguin plushie and is excited to learn that Nodoka regretted not learning her name. 40 43
• Miyanaga Saki — Rival mahjong player and later companion in holographic training. Koromo recognizes Saki as a powerful opponent and grows comfortable enough to approach her affectionately. 48 85 100
• Ikeda Kana — Opponent traumatized by Koromo’s dominating play in consecutive tournaments. 49 50 53

Notable Quotes

“Because when it's a full moon, I am invincible.” 2

“Being a Demon King is for mahjong skills, not for everything...” 15

“Maybe... Koromo can make friends now.” 56

Trivia

• Koromo prefers Chinese barbecue to yakitori and especially enjoys street food. 56 57
• She likes strawberry cake and strawberry milk. 43 109
• Her rabbit-ear accessory and petite appearance regularly cause others to underestimate or mistake her frightening mahjong reputation. 27 48