The YouTuber here must have really, really pissed off Hircine. He tried to become a Werewolf, but got trapped in this freakish, glitchy form that’s a little more man than werewolf.
The glitched form can use weapons, although not very well, do shouts, and can wear armor if you don’t mind some nightmare fuel. One leg appears to be mostly human. It also can’t die, as is the case will all truly unholy things.
The model is extremely glitched and contorted, but it kind of makes sense if you’re roleplaying the character as horribly cursed.