1. That barfalicious fat that hangs over the top of a person's pants when their jeans are a few sizes too small.
2. The most delicious and fattening part of a muffin that results in definition 1.
That girl ate so many muffin tops that she turned into one.
An example of you are what you eat.
When something unsexual reminds you of sex, or is so good it's like sex. Often delicious foods can be sextastic.