From Chibi Manga:
She's escorting boy to make them believe in love. Though she doesn't know anything about love, he'll teach her what "love" really means...

From Shoujo-Sense:
High school student Hotaru has never been in love. To her, it's a mysterious feeling, despite the advice of those around her, and she finds herself wishing she could experience it for herself... That is, until she meets Shinri—handsome, popular, and a shameless flirt—who offers to teach her about love. Could this be her chance to understand the mysterious feeling at last? And what, exactly, are Shinri's intentions?