I Can't Say "I Like You"

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.—"