Krystal Jung and Oh Sehun used to be childhood bestfriends back then when that accident didn't happened . Sehun's family decide to go to Seoul to forget about the incident and lived happily . Krystal never blamed Sehun for what happened until she knew that Sehun and his family decide to lived in Seoul , She waited for Sehun to comeback but there's no message or news she get until she grew hatred on him .