Wait! I've got an idea

"Wait Jack, I've got an idea!" you say

Jack quickly pulls out of you to make sure he doesn't cum.

"What?" he enquires

"Fuck Jennie while you lie on your back" you say

Jack does as he's told and Jennie quickly gets on top of him. As soon as he starts thrusting into Jennie's tight pussy you start fingering her asshole. You keep adding more fingers until your whole hand is inside her ass. You can feel Jack's cock thrusting inside her pussy.

"Stop thrusting Jack and just put your whole length inside her" you command

Jack does as you say and you managed to grab his cock through Jennie's ass

"What the fuck are you doing?" Jennie moans

You start jerking Jack off through Jennie's ass as he moans with pleasure

"Well this is a first for me..." Jack says