Honestly, this kind of niche genre (though I adore it) suffers from the same problems as the Breast Growth and Penis Enlargement files, only to a worse degree. Hypnosis, though it may potentially be effective in inducing physical changes, is not well known for being effective in that. Oftentimes, the breast growth or penis enlargement files just opt to provide the perception that "my thing(s) is bigger" instead of figuring out how to work around biology.
This kind of file has all the challenges of breast growth files, except smoke and mirrors don't work as well, since "Do I have moist nipples" is an easy test as to whether you are lactating or not. So, the hypnotist needs to figure how to induce actual lactation to get a success story. I'm no expert on this kind of thing, but maybe that explains the unfortunate lack of content compared "haha you are gey sissy nao. Succ penis 4eva lol"
Like, they're probably equally niche fetishes (lactation fetish is not as uncommon as you think in our society's rather breast-centric sexuality), but for some reason there's just so much more for sissyfags.
