‘FLCL’

A young boy named Naota is hanging out with Mamimi, the girlfriend of Naota’s absentee brother. Their relationship is an uneasy one, since Mamimi seems to enjoy teasing Naota quite a bit. Suddenly, their time together is interrupted by the arrival of a seemingly insane girl on a motorscooter. She runs over Naota and then whacks him in the head with her guitar…

Descriptions taken from AniDB.net