Oh no... my ex-boyfriend lives next door?! Excited to start a new chapter in her life as an adult, Hyejin gets caught off guard when she finds out that her first love Haejun -- whom she dumped five years ago -- is her new next door neighbor and fellow classmate at the same university! Still dazed and confused about love and dating, will Hyejin learn how to navigate her relationships with certainty and confidence and not get sidetracked by what others think?