I imagine that she's at an adult themed Christmas party just thinking:
"Hee hee heeee, I can't tell if that guy that is sitting alone over there drooling because of how huge and round my girthy gourds are, or how sweaty my pits get when I swing my massive mommy melons around like this. Either way, just seeing him get so aroused by staring at my body is making me wet.... He even looks almost exactly like my son. Even better...."