Chuunibyou demo Koi ga Shitai!, Kotoura-san Recommendations
Main Character suffers from a deep dark past but one day meets the person who will save her in the end.
In both series, one of the main protagonists suffers an event from the past and continues to faces it in present times.
Both series also takes place at a school setting where there is comedy, drama, and romance. Of course, there are other characters involved that stirs this up.
Both series involves a group of characters at school facing various challenges everyday.
Both series has random amusing scenes that comes from imaginations/thoughts.