Girls if you saw a dude with a straight up butt ugly woman, what would you think. Even though the guy maybe a good looking guy around an 8 (The reason I say I am an eight is because I am chubby so the body is not really there yet. Not like damn he is fat but still chubby).
i agree with the first anonymous answer, the guy in question probably thinks he's better looking than he really is. I doubt he's an 8..so lets say the guy is more like a 6, if he's with a butt ugly girl it depends...if she dresses nicely and you can tell she tries to look cute but just isn't genetically gifted I'd think she probably has a great personality or he's truly in love. if she looks frumpy, dumpy or nerdy I'd think he's using her