While a man is going down on a woman, inevitably he will attempt to make eye contact. The moment when the eyes of both parties meet, from the female's perspective, the man looks like an alligator lurking in a swamp; only his eyes peeking up to be seen.
Girl 1: So last night, Mike was going down on me.
Girl 2: Ya and?
Girl 1: Well, have you ever noticed how proud they look when they are down there and look right up at you?
Girl 2: Yea, kind of like an alligator peeking up from the water.
Both girls in sync: ALLIGATOR EYES!