Reia Tsubaki is a supporting character from YuriKuma Arashi. Kureha's late mother and was a teacher at Arashigaoka Academy, and a good writer. She was killed by Yuriika, leaving the pendant she received from her with Ginko. A gentle and affectionate lady.
- "The Moon Girl and The Forest Girl" is a love story without ending she writes and proceeds about the love between two different girls, which happens to be later her daughter Kureha as the Moon Girl, and Yurishiro Ginko as the Forest Girl.
- After she found Yuriika, she hugged her and show affection to her by telling her to forget her agony and open her heart to become true friends with her.
- After she became friends with Yuriika she showed her how nice and caring friends can be, and had some intimate moments with her.
- Under starlit night, When Yuriika asked her if she loves her she agreed saying that she loves her a lot and hold hands with her around the lilies garden.
- She encourages Kureha and Ginko to have a special friendship relationship with each other.
- "As long as you don't forget love, you'll never be alone. If you don't give up on love, even if you lose something, you'll never be invincible" was the lesson she taught Kureha and Ginko to overcome their problems.