Hello.

I am wondering what the lower limit is to call a post "explicit".
Like is it just words such as "I wanna get fucked so hard", or does it have to depict nudity or whatever in the image?

This image is an example. You may also want to read the translation for that post.
post #828781

Help: Ratings lists the basics, though borderline cases are always difficult to rate.

dicks, legholes, stuff that comes out of dicks and legholes, and the use of dicks/legholes regardless of whether or not you can see em

https://e621.net/help/show/ratings Is a general overview of ratings, and the best to follow. However, some people may have certain viewpoints on things, for instance dry humping is tagged questionable when I thought it to be explicit. So, for making posts and for tagging, it's usually best to just follow the ratings help guide, and if problems arrive, then just go get an admin. Their judgment is always final, no matter who agrees or disagrees.

Somewhat related: forum #192535