Joon-yeong happens to know that Yeon-ji is a virgin. He uses his junior Joo-won to break down Yeon-ji's air conditioner outdoor unit to seduce her. Yeon-ji and Mi-ho, who are tired of the heat, stay at Joon-yeong's house. The four of them are living together! Joon-yeong tries to seduce Yeon-ji, but ...