You should not post anything that would be considered inappropriate in a business or school environment (in other words, "Not Safe For Work"). Here are some examples:
Links to images or videos containing pornography, nudity of any kind, or sexualized minors (i.e. "jailbait"). Links to real-life blood and gore. Gore in a video game is fine, but real-life graphic material isn't. Hate speech, such as using race, religion, sexual orientation, culture, ethnicity, disability, nationality, or gender as a means of insult. Sexually explicit posts. If you must discuss sexual matters, keep it vague. The less detail, the less likely someone will find it offensive.
What part of your question fits the bill of "keep it vague"?