Feeling sorry for Mi-yeon, who is not interested in men, So-jin introduces her to Joon-ha, a friend of her boyfriend, Do-joon. Do-joon, who did not know this, falls in love with Mi-yeon, whom he meets by chance, and tries to seduce her. Then one day, Mi-yeon catches Do-joon meeting So-jin, and they end up having a 3-on-1 sex.