|Kanji Name||桜井 梨穂子|
|Romaji Name||Sakurai Rihoko|
|Date of Birth||04/12|
|Manga Debut||Chapter 1|
|Anime Debut||Episode 1|
Rihoko Sakurai (桜井 梨穂子, Sakurai Rihoko) is one of the female protagonist of the story, and her story is in the 5th arc. She is childhood friends with Junichi Tachibana and Kaoru Tanamachi. She is a student of class 2-B.
She has brown hair and brown eyes. She wears their school uniform, but she wears a vest rather than the black coat. Her attire is similar to Kaoru.
She has a huge appetite and is also extremely clumsy, forgetting things with unusual ease. Her best friend is Kanae Itou, who is an extremely athletic girl. She is often seen in the library, reading dieting books and also a member of Kibitou Tea Club. She has an unrequited love for Junichi ever since childhood.
In her route, she is portrayed as Junichi's childhood friend. She eats a little too much and believes herself to be fat. Has been with Junichi since elementary school and has a crush on him ever since.
Junichi spends Christmas with Rihoko and Miya in their house. Later outside, he tells her that he always took their relationship for granted, but now it's different. They share a deep, passionate kiss. Many years later in college, Junichi buys her a creampuff. Inside it, there's a ring and she accepts.
Junichi spends the school Christmas festival with Rihoko. He hugs and realizes how much she means to him. The next year, he joins the tea club but it's closed due to lack of members. Despite all this, she's with Junichi and that's all that matters.
Rihoko wakes Junichi up while in bed by jumping in his bed and going underneath the blanket. It reminds her of their childhood and the time they spent together and she feels that it will not change.
If Junichi stoods her up on Christmas, she forgives him. Junichi begs forgiveness from Rihoko (who caught a cold from standing in the snow) but she tells him that she was never angry at him and never can be. They proceed to kiss. A little while later, Junichi begs Rihoko to punish him. She makes him eat an all you can eat ice cream parfait. He faints and Rihoko smiles. They'll be best friends forever.
- Her Arc is the only arc wherein Christmas takes place in its third chapter and the only arc to feature the events after Christmas on-screen.