squareheadbuttface

Brownie points to whoever can identify said person:

X: You, my dear, can call me whatever you like.
Y: Really? Anything?
X: ok, ok, I meant anything within reason.
X: No reason to call me sqareheadbuttface or something.
Y: what?
X: I was poking fun at myself.
X: My chin is shaped like a butt.
Y: ???????????????????
X: It is a little. There's a crease in the middle.
Y: What?
X: So when I squish my chin
Y: Um...
X: It looks like a buttcrack.