Ono Natsumi manga
Ever since an childhood incident, Chiaki has never been able to truly feel joy or have fun. One day, his traveling father sends him a mysterious cardboard box. Once opened, a girl who calls herself Cerberus pops out of the box! This girl, who has three personalities in one, vows to protect Chiaki from all harm. Will Chiaki be able to live with this three-in-one girl?
Once upon a time, artists were able to use their special skills freely, until seven years ago with a group of artists began using souls as raw materials for their work. Now society lives in fear of artists as a young man named Acro Hamburger travels to the capital city to ply his trade as a sculptor and to realize his dream of becoming a great artist. (from wikipedia)