You just know Spy's gotta have a plethora of toxins and drugs at his disposal, for a variety of nefarious purposes. Perhaps part of how he's managed to "score" so much was with a little helping hand of a little something called rohypnol. Spy especially enjoys doing it to his enemies - rival spies, someone that's been a thorn in his side for his current mission, someone that previously rejected his advances, perhaps even his target he was supposed to simply kill or hold hostage but decided to have some fun with them first. And it's especially satisfying when he gets his hands on Sniper. Sniper's no stranger to Spy stabbing him from behind anyway. Perhaps even quite literally twisting the knife in somewhere nonfatal but bound to hurt a lot. Sniper promising to himself he'll get revenge on Spy soon enough, but for now... trying to piece together the memories of what happened and jerking off to it.