Cheotsarangeun Hate

Childhood friends Eun-Ha and Seung-Min used to be inseparable until Seung-Min started running with a bad crowd in middle school. That marked the end of their friendship, or so Eun-Ha thinks until she runs into Seung-Min again in college! As if that wasn't jarring enough, his appearance has done a complete 180, and Eun-Ha can't figure out why. Everyone thinks the former delinquent is a quiet nerd because of the way he dresses and behaves. But once Eun-Ha starts talking to Seung-Min, she gets the feeling that he hasn't changed as much as his glasses and plaid flannel would suggest...

(Source: Tappytoon, edited)