A "Zero width non-joiner" is classified as a punctuation but it's actually invisible and impossible to see or highlight. Vsauce used this to make a video with no title. You can also use this to use as a username in some site or game accounts, not all of them though. You can also use this to send blank Discord or whatever messages to confuse your friends and/or grief a Discord server ._.

P.S. Please don't do that. That would be mean...

A celebrity free pass is an agreement between you and your significant other that if you meet said celebrity and there is an opportunity to sleep with them, your partner cannot get mad at you for doing so because you had agreed before hand that this person was your celebrity free pass. It is ideal if both of you in the relationship choose a celebrity free pass so that the playing field is even.