Hyo Yi is a poor girl with a scholarship to one of the most exclusive private schools, attended only by kids from the richest families. Strong and resilient, Hyo Yi fights to protect her mentally handicapped brother whose illness makes him a target for bullies and beatings. Then she meets Min Ha, who unexpectedly winds up making an agreement to protect the siblings. Bound together by their unusual arrangement, Hyo Yi and Min Ha gradually learn what it means to love, one step at a time….