What is deviancy? An incomplete definition would compare it to what people believe normality is. Again, I believe there are few 'norms' in the fuller breadth of human sexuality. There are societal expectations. These define what is approved by the society and what is not. Those who step outside of the society's boxes are labeled deviant. This does not make their actions bad, but it does place them in a place of nonsupport by the larger society.
Sexuality exists in our heads. We imagine and create a sexual world that bears only a passing resemblance others' realities. I believe that only a small fraction of these imagining are related to others. We are not so incredibly special that only you or I have a unique sexual thought. There are sexual "archetypes" that are not fully expressed by those who feel them. These archetypes are physically expressed when willing partner(s) are found. I believe that many of us walk around frustrated, our imaginings kept only to ourselves. The mantras of "don't do it" push these desires deeper. Those who deny the physical expression of their desires and continue to feed them internally run the risk of a "exploding" in some inappropriate or destructive way. I say that sex in the head may not be 'real, but it does have a drive and voice that must be addressed for the person to have a healthy life.
Sexuality exists in congress with others. I am a fan of consensual activities. I also believe that there is a place of hygiene, compassion and acknowledgment of life contracts. Hygiene speaks to being responsible and mature. Compassion adds an emotional component to the maturity. Life contracts are those agreements we have with people. Sexuality can create energetic bonds. We establish contracts with others so that bonds are guarded and respected. Simply put, don't make any promises you can't keep when it comes to sexual relationships. All of this rolls up into something I will call sexual integrity.
Sexual integrity is important no matter how 'deviant' the behavior is. The irony is that more extreme deviant behavior requires more sexual integrity. Deviancy moves people away from the norm of the bell curve. Reliable and matching partner(s) become more difficult to find. Those who are compatible are entrusted with the knowledge that the person is outside of societal norms. So, there is a reputation aspect as wells as any associated health issues. In my opinion, sustained deviancy requires more maturity than sexuality experienced "in the norm".
I'm a deviant in my own ways. I strongly suspect we all are. This is not important, as the measure of deviancy can be an artificial creation of the society or tribe. How can we turn those 'deviant' thoughts in our heads into reality? Find a tribe that supports your appetites. Then honor yourself and others. Sexuality is only part of a larger life. The healthy pursuit of your sexuality, no matter where it will take you, is just a part of who you are. Be safe, have fun, and celebrate complexity.