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I am looking for the name of yaoi where a boy lives with a hitman who he believes killed his parents but who is actually protecting him. The hitman leaves him locked in a room so the authorities can take him out of that world. The boy escapes and shoot one of the social worker. He starts working with the mafia and he found out that they killed his parents, in the and the hitman saves him.

Can you help me in my search?? Thnxs!