Shokujin Ki

-The Man-eating monster
　The protagonist is a man-eater in the form of a young man.
　Each time he eats someone, he remembers his or her memories and gets closer to human being.

-A girl willing to die
　"If you don't mind, will you kill me?"
　A mysterious girl doesn't say anything. She just wants to disappear from the world.

-A story of irresistible hunger and despair
　As the monster interacts with the girl, it learns about human beings and suffers.
　The cannibal's instinct tells him that he is still hungry, and the girl begs him to kill her.
　And the final decision is imminent.

[From Steam]