A cheesehead is someone who eats lots of cheese and has a triangle shaped head.
You could also refer to them as Chester Cheese.
"Wow I am such a cheesehead, I think i'll go play neopets for a while and eat some cheese"
"My roomate Mel is such a cheesehead"
"Chester Cheese is such a kool kat!"
A - I gotta pay rent, but my girl want a Birkin.
B- Huh? Have u even hit yet?
A - Nah bro, she said she isn't ready, I'm just keeping her happy.
B - You are afucking Cheesehead.