Anthony Michael Hall
Some people say he's a little too cool and witty in this for such a nerdy outcast character.
shareI can see that, but then again look how awkward and clueless he is when the girls enter the bathroom, he has no idea how to talk to them, and they both then go hide in the shower together.
He also has overbearing parents who have made him a submissive weakling, and you remember what a prat he made of himself getting drunk in that bar.
He was a cool, confident guy in waiting who just needed that extra push from Lisa to grow a pair of balls.