Should I ask him out, if so how?

Yea he likes you for sure he is just real shy and stuff. You should ask him out only if you like, and the how is simple guessing that he is unpopular means he would not be surronded by firedns so it should be easier to aks him one on one just come over and say can i have a min with i need to talk and just ask him out.. Anyways good luck