A Beautiful Affection summary: Ji-woon falls in love with Se-jin from the same university and confesses once a day. Se-jin has refused to confess, saying Ji-woon will not like his tendency.However, the two love become lovers at Ji-woon's words, which promise not to leave the side no matter what happens. Ji-woon is happy to be close to Se-jin, but at the same time, Se-jin begins to reveal her secret and sadistic tendencies as time goes by. In-hyuk, who had a crush on Ji-woon from the position of a friend, recalls Se-jin's past and tries to piggyback Ji-woon. Inhyuk goes around Jiwoon and fights a war of nerves with Sejin Friendship, love, desire.Romance on a crossroads with mixed arrows of emotions!