I had never seen her being fucked like that. He was an animal. He held her ass like a vise and I could see his huge dick penetrating her.  He pulled it out, rubbed her asshole with it, then plunged in again. She was so wet it glistened and when he shoved it into her it made wet sounds, his balls smacking her with every thrust. She cried and came and cried and came and the sweat was running off his chest as he worked her harder and faster.
"Fuck my mouth!" she cried to me.
"Fuck my mouth Ulf! I want your dick in my mouth, I want you to come in my mouth while that black beast is banging me. God, he's so good!"
I stood in front of her and zipped down as she opened her mouth, moaning and drooling.
And I fucked her.