"man's chastity belt" by: https://civitai.com/user/Hinder

https://civitai.com/models/12508/mans-chastity-belt

About this version: This Lora works well on AOM3. It can also be used in other models. However, if used in other models, the shape of teticles may be slightly distorted. I recommend you 0.5.

You should put small penis, teticles, chastity belt, otokonoko, 1boy, in the prompt.

And also you should put things about women(ex. woman, girl, breasts..etc) in negative prompt

Uploader note: Author didn't set any allow/disallow permissions on his page, so I'm just setting it to personal use and sharing. Also, "testicles" is misspelled as "teticles" on the page and tags of the source.