If you want something that'll never change policies on you, host it yourself. Either locally or by paying a hosting service. The trick is finding a hosting service that's ok with erotica. I know nearlyfreespeech.net will do the trick, if you're ok with the pay-as-you-go idea. Gandi.net might be too, though not entirely sure.
The vast majority of hosting sites you find advertising for $5/mo do not support nsfw material of any kind.
If you need tips to get started hosting it yourself, let us know. The basic version is install wordpress, install something like Zenphoto (or many other excellent image apps,) and then start uploading
