Hey, You Stole My Heart summary:

Seowoo falls in love at first sight with Lee Chungha, a hyung in his church. His abrupt confession is met with rejection because Chungha doesn’t want to date a kid. Chungha tells him he’ll reconsider it when he turns twenty, so Seowoo blindly believes it and follows him to college. However, he has absolutely no idea how Chungha actually feels…