|坂井 理奈||Sakai Rina|
|Birthday||November 8th, Scorpio|
|Anime||A Cherry Blossom-colored Beginning|
Rina has peach-coloured hair, with a red bow-tie hair clip on top of it. She is about the same height as Mitsuki.
As vice president, Rina is Mitsuki's loyal assistant and respected among the members of student council, especially Kaede and Sumi. She always have a smile on her face.
Rina is hinted to have romantic feelings toward Mitsuki and follows her every word. One example is when Mitsuki once mentioned she likes to eat pudding before studying. Rina also started eating pudding and inadvertently started a pudding-eating craze among third-year students.
- Voiced by Yurika Endō.
- Her symbol is her bow-tie hair clip.