All things being equal, since Lucifer has been inside Sam, Sam should know what it feels like to be inside Lucifer.
It feels… soft. Lucifer's guts contract around Sam's intruding cock. Pulling out, it's coated with Lucifer's blood, and the gash Sam was fucking is ragged and wet. Lucifer pants heavily.
"Don't move," Sam says, like Lucifer has a choice, Enochian handcuffs chaining him helplessly for Sam to use.
"Sam, please," Lucifer whimpers. Whether it's pleasure or pain is impossible to tell.
Sam presses the head of his cock to the wound. It pulses, inviting him to fuck it harder.