Tokyo Ghoul, Vol. 1

Shy Ken Kaneki is thrilled to go on a date with the beautiful Rize. But it turns out that she's only interested in his body—eating it, that is. When a morally questionable rescue transforms him into the first half-human half-Ghoul hybrid, Ken is drawn into the dark and violent world of Ghouls, which exists alongside our own.

Volume 1 of the Tokyo Ghoul manga series by Sui Ishida.