My Tentative Name

Our protagonist awakes in a house he doesn't know—in fact, not only does he not know where he is, he doesn't know who he is. What he does know is that this unfamiliar house is empty, save for the body (and head) of a decapitated woman—a stranger, he thinks. He’s rescued by a woman, Shio, who calls him "Iori"...but is that who he really is? And when she helps him hide the body without batting an eye, telling him to trust her...can he? Should he?

(Source: Kodansha USA)