Other name: 恋BOOK, Koi Book, I can't say "I like you", “すき”と言えない, “すき”と言えない。
Summary: Shiina has 2 secrets. She loves her brother Kiri a lot, and Kiri doesn't know that they are not blood related. She doesn't know what to do, she's been hiding it for a long time, and no one knows she loves him. "This love is secret. Secret to anybody. However, my heart is trembling. ---Hey, I've become aware of these feelings. Please don't notice.---"