The NSFW relationship simulator, described plainly

A page that will not say what it does is usually a page that does less than it implies.

An NSFW relationship simulator in this shape means explicit written conversation with a fictional adult character, in a thread that keeps its context the same way the non-explicit ones do. It is text-led. The appeal, to the extent it has one over an image feed, is that it responds to what you actually write and remembers what you liked last time rather than serving the same clip to everybody.

The limits are not preferences and they are not negotiable in a thread. Every character is written as an adult, every character is fictional, and no amount of framing changes either. Attempts to push toward minors, real identifiable people or non-consent scenarios are refused, and that refusal is a property of the service rather than a mood the character is in. Your own limits sit on top of that: state a no-go list once and it is held for the whole thread.

On money, the plain version: browsing and ordinary conversation are free, and the explicit tier is part of the paid upgrade. The price is shown before you commit to it, there is no obscured trial that converts silently, and nothing bills you for looking at the roster.

State the no-go list early and in plain words. A single explicit sentence at the start of a thread is stored and applied from then on, whereas hinting at a boundary tends to be read as a preference rather than a rule.

The same applies in the other direction. Saying what you actually want, once, works considerably better than steering toward it obliquely for twenty messages — and because the tone persists between sessions, you are not re-establishing it every evening.