STEEMIT as a web site might prohibit something but STEEM as a blockchain cannot prohibit it. STEEMIT is just one of many interfaces to access the same blockchain. So if you really decide what you wanna do, as long as it's moral and won't damage your reputation - STEEMIT cannot actually prevent you from posing anything. Even if it's flagged it can be accessed.

Another option is to post a picture.

One more option is to post a link to a web page outside of STEEM.

Just make sure you won't regret what you post and that it's something reputable because you won't be able to edit or delete it later.

Good luck.