Sure, people dive their face in and eat it.
But face it (pun intended), ass is nothing like cake.
Ask a pastry chef, and he or she will agree.
A cake has layers, a cake has delicious frosting, and a cake definitely doesn't bounce.
Comparing buttocks with scrumptious moist cake should be a sin in its own.
I for one though, would decorate an ass like I would a cake, whip cream, candles, icing and all.
But it's still an ass. Case closed.