You tell Emma yes, you want to fuck her.

You tell Emma that you do want to fuck her and she helps you quickly shed your clothes.

In the hallway outside of the living room Emma places her hands against the wall and spreads her legs. You're still mostly hidden from view from everyone fucking in the living room when you move behind your girlfriend and grab her by her hips.

Your cock is hard and sticking straight out. You poke around at Emma's ass before finding her cunt hole, which is soaking wet. You push the head of your cock up inside of Emma and fill her with your entire length.