With this LoRA I tried to focus on the features of a well-trained female belly. I used a set of 58 photos and trained it with the PicX real model. It should work with standing and lying poses as well as realistic and non-realistic models.
Now available for SDXL! -> click here
It works best with a strength from 0.6 - 0.8. Use the trigger "btfembelly" to activate the LoRA. Possible additional keywords are: navel, belly button, linea alba, lateral abdominal lines, hip bones, Apollo's belt (make sure to add "belt" to negative prompts) or V-cut, pubic mound. You may also try "vertical belly button" or "round belly button", but that might not work reliably. See below picture for reference.
Don't forget to share your images, I'd love to see what you have created. And if you have a few minutes left, make sure to have a look at my other LoRAs. Happy prompting!