"Wow babe you do that like a pro. Is this the first time you've ever sucked a dildo?"
(You blush with embarrassment.)
"I hope it doesn't bother you that it's bigger than your own teeny weenie. Actually, I bought this one because it's small enough so that when I show it to a guy his confidence shoots up and he feels like he can really satisfy me. I never imagined there'd be any guys who could be so....
Ahem well, what I mean is because this dildo is so incredibly small I thought...
I guess what I'm trying to say is...
...that you have a humongous penis hahahahaha!"
(You feel totally humiliated.)