Millie is annoyed

"Why did you let her win?" Millie leans towards me and whispers angrily while Patti is out in the kitchen.

"Sorry, you had me really close right before but then you switched with her." I whisper back.

Trying to be smooth, I also add:

"Plus I'd rather fuck you in the ass than fuck her in the ass."

"You could fuck me in the ass some other time!" Millie whispers back, very annoyed, then continues: "Now I will end up suffering the humiliation of being fucked in the ass in front of my older sister!"

I can hear Patti on her way back from the kitchen, and Millie can as well, so she leans back and says quite loudly:

"Wow, that was a close contest, don't you think Matt?"

"Yes, in a way you are both winners." I reply.

Patti heard us and starts to laugh as she enters the room. She sits down on my other side, pats me on the thigh with her hand, then says:

"Tell you what Matt, in life, 'winners' don't get fucked in the ass after the contest."

Patti starts laughing again, I want to laugh as well, but suppress it since I can see that Millie is fuming on my other side.

I want to say something, but what do I say?