FLUX Kontext version: I created this because Flux usually doesn't get this concept right so I created this LoRA as a helper. I made it with Kontext so it can hyper-focus on the specifics of own lower lip biting - however I noticed that it sometimes does change other facial aspects on occasion, so I still consider this a work in progress / 1.x version. It seems to be random when it does that or not. I'll work on that with future versions, but for now if it's changing too much else, then you can further specify 'while maintaining the same facial features, hairstyle, and expression' or similar in the prompt. If it's still changing too much of the other parts of the image, then a sure fire way to stop that is to just select the mouth or face area, assuming your UI lets you do that; I primarily use Krita - not sure how to do it in ComfyUI but I seen YouTube tutorials showing that it can be done. I believe some versions of A1111 can as well.

Adjusting the weight above 1 seems to help if it's being stubborn on any given image - however if you do that, I recommend isolating the mouth area with a mask if you want to keep other facial consistencies.

Some checkpoints are able to produce the concept of an individual biting lower lips well. Some -- not so much. There are LoRAs that address this either by helping the initial image generation or through inpainting, but the ones I've tried seem to be trained a lot of women so when using it on a dude it doesn't help so much outside of gender-bender scenarios (not judging!)...

So I created this one to help, at least me, with creation of images of dudes biting their lower lips. It can be used reasonably well on initial image generation or better yet as an inpainter.

main trigger word: bitinglip