'Promotion' (Lee Ji-hoon) is preparing for an audition for his dream of becoming a singer. The moment I was about to spend my first night in a room I bought with my best friends, I heard a woman's cry from somewhere! The true identity of the sound is the sabotage of 'Rani' (Han Seung-yeon), who kicked out the next door family who moved in in various ways because of the house with no soundproofing! But promotion was no easy match! At the end of the extraordinary noise war that goes back and forth over the wall, living together rather than sharing time begins! Sharing each other's daily life without knowing their names or faces, they are increasingly caught up in subtle emotions... Bloody sweet new concept iron wall romance! There is no time to rest or love, and there is no gap between us. This must be the first relationship like this?