A step down from being "Pussy Whipped"; refers to when a man who does not have the freedom to do as he pleases on account of the pussy being so damn good.
"Hey man, wanna throw some g's at the club with us?"
"Nah, I gotta stay home. My psychotic wife is putting out tonight."
"Shit man, she's got you in a penis fly trap."
Laying down, an unwashed phallus is used to lure in flies. Foreskin is pulled back waiting for flies to land. When they are in place the foreskin is quickly pulled back over the knob trapping flies within.
Laying back, penis in hand hoping to catch these flies with my penis fly trap.
Another word for a vagina
TJ: I can't believe my breeder roommate is into vaginas.
Joe: Yeah, I know! Those penis fly traps are scary.
TJ: Good thing we're gay.