I think what you're referring to is MFM not MMF, as that signifies the other guy will swing both ways, so if you're not into male on male, then your really mean a MFM as that's a threesome where the woman is the focal point.
Are you looking for plot based (some story) or just gonzo (no story?)
There's a 3-way in Little Girls of the Streets - so NOT what the title of this is, as it's all 70's and 80's women, pubic hair, and lots of unprotected (no condom) cum shots. It's very weak on the story line, but it makes up for in spades with the scenes. Scenes are great too - they're not your 2000 era 25 minute sex scenes that put me to sleep...
Another one is Decadent Desires - it's got a mix of MFM and FMF threesomes and even a foursome outside with a redhead. It's a Marc Dorcel special...
If you're into foreign films, you can check out Madame which has a few MFM scenes, but actors use condoms and do the tear off and shoot.
Something recent that has a MFM scene is in Body Heat. This movie won a tonne of awards, but I actually had a hard time getting through it without dozing off, as the sex scenes went on and on and ON - We actually fast forwarded through some of the scenes as it was just way too long. The MFM scene in here is a shower scene with the fire captain (female) and 2 of the firemen.
We actually watched a movie last week and it surprised us with the most amazing MFM scene and even my wife commented that "it looks like she's having fun". Unfortunately I can't remember the movie title - if it comes to me, I'll reply.
I really wish this current era of porn would do some MFM scenes. I've love to see New Sensations, which is a studio famous for their plot-based porn, come out with something that has a MFM scene (ideally it would also be great if they had different actors, as I'm getting tired of seeing the same ones re-used in every film).
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