I'm of the opinion that as long as you aren't hurting yourself or others without consent, do what you want to. The consent thing is important because people will play contact or combat sports, do BDSM stuff, etc. - so long as it's informed go nuts. It's also important because some people can't give informed consent, e.g. kids can't agree to underage sex because they don't know about the harms and are more vulnerable to manipulation.

A couple of years ago I watched a doctor review a video of someone who likes having sex with balloons. The doctor said he would only diagnose that behavior as a problem or illness if it was hurting him or others around him. His argument was if there's no harm and it makes that person happier then what really is the problem? I was initially taken aback because it's weird right? But after some thought it really made sense to me - just because I don't relate doesn't make something bad. I don't have to want to do it myself - there's room in life for multiple (non-harmful) preferences.