A romance about childhood friends, mutual pining, and physical chemistry coming first. Lim Ji-u and Go Jae-jun have been inseparable friends since kindergarten. While they seem like ordinary friends to everyone else, Jae-jun has secretly harbored a crush on Ji-u for a long time. One day, Ji-u, who falls in love easily, confesses to Jae-jun that she has a crush on his older brother. Upon hearing this, Jae-jun makes a provocative proposal: 'My brother likes unusual things and sexy women. I’ll teach you how to be his type.' The two set off on a three-day trip to learn these 'unusual things,' where Ji-u discovers a side of Jae-jun she never could have imagined. 'It’s too big! Is this even human?!'