I agree, I think he's obsessed. Bad juju going on here.
I'd feel differently if, after you told him, he was like, "Oh, hey that's kinda cool! Tell me about the process, etc" instead of talking about wanting a girl with "an extra part" right up front.
I vote no, drop him, just say you're not comfortable but will keep his number/name, etc in case you change your mind. (Don't give him yours)