For luscious, obviously fake lips.
Face Restoration may turn the fake lips into a mustache/"monkey lips".
To avoid this, you can change/lower/disable the face restoration setting or first generate the model then paint over the lips with face restoration disabled.
Or generate first without face restoration, then with face restoration then combine in photoshop/gimp.
Used in examples: SD1.4 / UberRealisticPornMerge / Clarity19