Oh no... my ex-boyfriend lives next door?! Hyejin is excited to begin a new chapter of her adult life, but she is caught off guard upon discovering that Haejun, her first love whom she dumped five years ago, is her new next-door neighbor and a fellow classmate at the same university. Still dazed and confused about love and dating, will Hyejin learn to navigate her relationships with certainty and confidence, without getting sidetracked by what others think?