If it's true behind your back cheating, it shouldn't matter if it was a snail's dick, or a donkey's python.
She's a liar, totally non-trustworthy, & certainly not worth commiting your life too.
NOW THEN- if it's swinging, group sex, or cuckolding that's being contemplated, you gotta play the scenario out in your most vivid of imaginations- & see if you could handle that kind of thing after play time is long over.
May I suggest trying out some fun with her, using an EXTREMELY large toy on herself?
Have her smash up that wet hole very aggressively, giving her deepest openings a total no-mercy workover, with the absolute biggest penetrating toy you can find - both in length & gerth.
Make sure she hammers the hell out of herself with it for a pro-longed period of time, while you watch the carnage unfold.
If this type of playing around makes you insecure in the least, you're in no way cut out to take the next step, of introducing some well hung stud-horse into you & your girl's sexual fun. And of course there's not a damn thing wrong with that; it's certainly not for everyone. Some of us get a hard-on just thinking about it though
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