Poe AND Pava were on the mission to Jakku. They both get taken by the First Order. Rather bored with their prisoners now that they've gotten what they wanted out of them, they give them a choice.
Option 1: You fuck each other, make it a damn good show, and we'll let you go.
Option 2: You refuse, WE fuck you both in very unpleasant ways while the other watches, then we kill you both.
Poe and Pava decide "hey, we're buddies, we're both attractive, and we both want to live, so let's just get this over with"
Poe/Pava, fuck or die
Option 1: You fuck each other, make it a damn good show, and we'll let you go.
Option 2: You refuse, WE fuck you both in very unpleasant ways while the other watches, then we kill you both.
Poe and Pava decide "hey, we're buddies, we're both attractive, and we both want to live, so let's just get this over with"