Akito & Karisa~

Hi, I will be writing and improvising a story about an anime boy, named Kirisuna Akito. He is a teen boy who has no interest in life, he thinks that all that's around him is nothing but emptiness with no one to be near and no one to care about.
He was tired of life and wanted to just end it, when just one transfer student came to his high school. This one girl wonderfully changed Akito's point of view in life, and she seemed to know a lot about him, and Akito finds out what the truth of all of this was......
Who really is this girl?......