Slow Thinking (a challenge to OOT)

[Matty]

Situation:

You're having sex with someone's girlfriend. Said someone could easily kick the ever-loving piss out of you. Said someone knocks on the front door of his girlfriend's 5th floor apartment during said sex. Said someone knows the girlfriend is home, so said someone's girlfriend insists on opening the door. Since it takes so long to get dressed and open the door, said someone will be very suspicious by the time the door opens and you won't be able to just sprint past him to safety.

There is no other exit from the apartment, and nowhere to safely hide. Assume if said someone suspects you of [censored] his girlfriend, he will kill you.

Assume said someone is of above-average intelligence.

How do you talk your way to safety?