"Promise, do you keep it well?"'Tae-seok' makes a living on a daily basis"'Soo-hyeon' can't keep up with her growing debt"'Ji-yeon' keeps getting on the wrong path" The three people who are on the edge of the cliffSweet whispers that cannot be rejected A contract with the devil with life as collateral!The moment you break your promiseThe endless curse unfolds!

Lea, a 23 year old university student, meets Ryan, a mysterious and charming man. Although Lea has a boyfriend, she lets Ryan seduce her. The next morning is a rude awakening, as what initially appears to be an attempt at blackmail turns into an exciting odyssey into the depths of the human soul, where Lea and Ryan have to take responsibility for their actions.