What is wrong with him?

So my friend likes this guy who apparently doesn't like her back. He's a football player at her school, who is a quiet guy. When she starts talking to him, he would stare at her for a couple of seconds, look away, and walk off. One time she tried playing footsie or tried to touch his backside, and he would either say knock it off, or say stop it, or push her hand or foot away. One time they were lab partners, and she accidentally got some info wrong and they got a pretty bad grade in which he said that she mislead him, and went and asked the teacher to either switch partners or go solo. She was crushed after that. He seems like a good looking guy according to her and by a word of mouth from quite a few girls, so could it be he's stuck up, or has family issues?