Wooyoung and San are assigned to the same human.  Wooyoung is an Angel assigned to protect him, while San is a demon assigned to kill him.

Yunho waited for them knowing they'll show up like they always do. When he saw them, he decided that today will be the day he'll face his crush and ask him out. It also helped that his best friend was dating his crush's best friend. 

When Wooyoung, the most popular boy at school, sees the same cute boy at his every competition/practice, cheering him on.  One day he decides to approach him 

When Prince jungkook is to be married and a selection is organized. Jimin, a dancer, is forced by his family to sign up, unknown to them he's already dating someone.  "Will I find love?" "You don't find love,  love finds you."

San is a Batista in hwa's coffee shop. Evey day he sees the same guy and they exchange a few words. What happens when one day the cute guy asks the Batista  out? Or When Wooyoung lost in a bet to Yeosang, and now he must confess to his crush?