Seol Jaeha has had a crush on his childhood friend Lee Hyun for a long time. Since the day he transferred, Kim Doyoung has been interfering with Jaeha and Lee Hyun, though it is unknown why. Jaeha and Doyoung are not in sync! The three of them continued to stay together despite their quarrels because Lee Hyun had wrapped Doyoung up. Meanwhile, Lee Hyun went to the countryside during the vacation and stopped taking supplementary classes, and Jaeha is happy with the thought of finally being freed from the fiesty Doyoung since Lee Hyun is absent. But Doyoung keeps getting caught off guard in class...