Nasol

A one-sided love is like a slow-acting poison—you know it's tearing you apart, yet you can't stop coming back for more. For 5 years and 120 days, Jung Dahee has been hopelessly devoted to her childhood friend, Lee Beomseok. Rejection has become such a regular part of her life that she almost expects it, but she's determined to change her fate with one final, heartfelt confession on the day of the CSAT. Everything was supposed to go according to plan. Until she accidentally discovers a shocking secret: the boy she's loved for years is having an affair with none other than her own older sister. Original Webtoon: Naver Webtoon, Naver Series

Yoojin is bad boyfriend material. It's partially because he never takes anything seriously, but it's also because he's never had a great time in bed with anyone. After being publicly dumped, he's approached by Hyeonsoo, an old high school classmate who also happens to be Yoojin's first love. After a round of drinks, they spend a heated night together that might have been a great time, but Yoojin remembers none of it. Torn between denial and desire, Yoojin has to decide whether he's serious about Hyeonsoo... which would be a lot easier if they could ever have a proper conversation.