I'm not a fan of bubble butts, but I do find I like "out of the ordinary" looks such as:
- very tall
- loads of inkwork (can't explain this one, lots of really nice inkwork is a big turn on for me)
- anything that creates a scifi type futuristic and / or slutty look, so nice bolt-ons, certain body modifications, and I love false eyelashes
- very slim
- very big
- flat as a pancake chest
- T-girls
Having said that, I've also loved quite a few natural boobs, both small and large