We enjoy mfm fun with a guy we know semi regularly. I'm 6+, he 8+ easy. It's very obvious she likes sex with him and yea the size of his dick is part of it. It's the whole aspect that's fun for us, watching each other, taking turns doing her, kissing her, her looking at me as he fucks her, she'll kiss him as I do her, etc.
Yea she's way more adventurous when he's with us, she does things with him and me she normally doesn't, when it's all 3 of us, she gets turned on like crazy. Anal not a problem, sucking a dick after it's cummed in her no prob, swallow a a load, no prob.
He's a skinny nerd type, big dick, he looks hot standing there naked and hard. I've been doing her, him standing next to the bed watching, she looks at him and she moves different under me. I let it go....she wants him right after. He slides in she just moans.
The size of his dick I'm sure does matter and I do know if we did it with a different guy, small dick if it all worked out it would be fun. Black guy, huge dick, might work, might not, would depend on a lot of things....the guy...where we were....our mindset, etc.
It's a fun time.