That person you meet who's a fucking weirdo but also seems like they might kill you. If they seem normal but like they might kill you, they're a psychopath. If they seem weird as fuck but otherwise harmless, they're weird. If they're both fucking bizarre and vaguely homicidal, they're a fucking weirdopath.
"That shitty weirdopath hobo invited me to stay with him under the bridge tonight; I declined."