The Sexy is designed for those who like high-waisted and slightly indented panties. Depending on the size of your bust, it will sit more or less under your navel. The elastics on the sides free the hips and give it a sexier side.
The Mimi is a classic, slightly puffy cut.
It is designed to be worn low-waisted but everyone is free to position it wherever they want.
These two models can be made for the female or male gender, it's up to you to specify.