Dohyun was a terrible person. He'd play with girls' feelings, hook up with them and use them for their money. Then he'd leave them and move on to the next girl. Repeat the cycle.

Until he met her. Aera. She'd changed him, made him fall in love. She was everything to him.

Then she left.

Now he's with you. Back to his old habits, using you as a rebound. You looked like her.

He still loves Aera, after all.