It's also important to remember that the days when performers were okay with anal creampies is long gone. More often than not most of those are fake because it is one of the unhealthiest things you can do in porn. By extension multiple creampies is likely fake for the same reason.

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Scene I'm imagining has the woman is doing a lot more than just waiting to drink the creampie. There is lots of bi porn out there with two men and a woman with the guys fucking eachother and fucking the woman, but I have only seen a few with a2m and none with felching. But I see tons of felching in straight porn and gay porn but not in bi MMF porn. I also have seen lots of trans porn with MFT threesomes, with everyone fucking everyone. But again those don't seem to have much a2m and zero felching even though I've found plenty of a2m and felching in straight and gay porn without trans performers or bi male performers.

One thing you mentioned: "Two guys having sex with each other is still gay porn even if there is a woman participating in the scene so unlikely to appeal to most hetero porn fans and I'm not sure if most gay porn fans want to see a woman be part of the scene either so why make porn that will not sale?"
If this were the case, then why is there so much mmf bisexual porn available? I can find PLENTY of MMF scenes with everyone fucking everyone but no A2m/felching. And all the safety stuff you said is true, but at the same time you find plenty of a2m/felching in straight porns and gay porns (if you look for it). You said a lot of it is fake, which may be true, but then why don't they just fake a2m and anal cream pie eating in bisexual/transexual porn too, the same way they do it MF and MM porn?

I just want my MMF, MT, FT, and MFT porn to be as disgusting and depraved as my MF porn!

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I get the feeling that what you are looking for is less about actual porn being made and more your type of fantasy porn that is simply not being made at all. I wish you luck because I doubt you will find much for the stated reasons. You might want to check older Italian porn because tghere was a time when they used to shoot a fair amount of videos where there is a mix of men, women and TS performers interacting with each other. Can't say if there are creampies but I doubt it.

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