BITTER×SWEET BLOOD

is a Japanese light novel series written by Suo Tsukasa, with illustrations by Chiyoko. The series began publication on May 10, 2007 by ASCII Media Works under their Dengeki Bunko publishing imprint.

Synopsis
I was bitten in the neck in the dark night. A popping sound echoed, and a red ball ran down my skin. That is the beginning of my relationship with him. He disturbs my heart violently. Every time I meet him, every time I exchange words, every time I stare at him, I get thrilled and thrilled. You can't stand just by touching a part of his body. ... Yes, he is "special" to me. -A "person" who sucked my blood. "Dark genus" dance mysteriously on the stage of the present age.