Riku Tamaza, a somewhat normal 18 year old boy, and yet the most wanted criminal of all time. Riku is an assassin, and a good one at that. His kills are always silent, the bodies never found, and never a trace of evidence is left behind. He only works for the clients that mean business. However; Riku's entire life changes when he's told to assassinate his best friend, the only memory of his childhood he has left. A single sliver of uncertainty slips into Riku's mind, something that's never happened to him before. He can't just kill his best friend, his only childhood memory... Or can he?