Before the Grapes Ripen

Due to an incident from his childhood, Tae-eun's father owes a debt to Su-young's family and sends them 1 million won every month.
Years later, as adults, the two meet again—he as the newly appointed team leader and she as the youngest member of the team—and navigate a precarious corporate life together. 
"Team Leader, why are you so nice to me?"
"Because I owe you."
"Then why do you hate me?"
"Because I'm not sure if it's my debt."

Original Webtoon:
Naver Webtoon, Naver Series