I'm going on a long break lmao

A miracle is about to happen to an unattractive loner boy... And his adopted sister. Belle was childhood friends with Daniel. Then, at the age of 6, her parents died. They were in an airplane, and someone had put bombs on the plane. She was adopted by Daniels mom shortly after. She was so happy that Daniel would be her brother. Daniel was sad, though. He never got to tell her that he liked her. Soon, he forgot his feelings. Will they come back? Will he have rivals? (I read this on Webtoons, so I use the English Translated Names for the Characters!)