I prefer to hide playtime and set myself to Invisible when playing lewd stuff so friends aren't notified. That way people can still see my library and games in common as well as Now Playing status while I'm Online. The only issue is that these games are still visible if someone searches my library, but I don't really care about that, I'm pretty vanilla.

Considering Steam has so many NSFW games, it would be great to have a proper "hidden/invisible" category that keeps ownership and all info about these games private while leaving other game info public. Perhaps also an optional PIN to access them so you can share your PC with friends and family without them seeing your lewd stuff. The current "Hidden" category isn't sufficient.