Concept of cock outline in pants or actually sock for cock.

Main triggers are (can be used separately):

large flaccid bulge, penis under clothes, penis visible under,

Lora strength controls size of penis, size of bulge, and intensity, but that depends on model used. Base doesn't respond in same way as custom ones.

To get actual bulge lower strength of lora (0.1 - 0.4), to get more pronounce effect rise it (up to 4 works, but this top is model dependant).

This is based on Krea2 Lora posted by @Zenpand located here: https://civarchive.com/models/2756401/large-flaccid-bulge-futanarishemale-krea-2?modelVersionId=3101552

Images contain workflows.

Generated using multiple based models to test this out, works well enough.