Sexual perversion is to be defined as sexual behavior that is not practiced by the clear majority of humans in a given culture that is differentiated from sexual exploration by the reoccurrence of the behavior, the extremity of the deviation, and the harm resultant from the performance of the perversion. It is recognized when a certain individual expresses certain sexual desires or urges that are uncommon, unrelated to typical sexual interactions, and/or are somehow outside the two categories entirely. Perversions are many and varied, diverse in their characteristics – varying from sexual attitudes towards non-sexual objects, to frotteurism, transvestitism, and voyeurism.
As human sexuality is diverse and highly variant between different individuals, so are sexual perversions. One such perversion is the practice of having sexual attitudes towards non-sexual objects – which are naturally themselves wide-ranging, and come in many variations, with possibly any object being the subject of sexual attitudes by a given individual. By Ruddick’s definition of perversion, given the fact that sexual attitudes towards non-sexual objects do not involve living persons of the opposite sex, they would certainly fit into the definition of perversion.i [1975a, 23] Although “objectum sexuals” are differing on whether they are attracted to objects exclusively or whether they are attracted to non-sexual objects in addition to more traditional sexual attitudes, reoccurrence is notably high in most individuals in the sense that they have repeated contact with non-sexual objects.ii [2010a, 13] The distinction from sexual exploration of these individuals on this definition is the difference of having a singular, or at most, limited repeated experience and a frequent practice that comes to replace, at least partially, sexual interaction with other persons. If normal sexual practices are to be defined as sex acts that “serve or could serve the evolutionary and biological function of sexuality, involves living persons of the opposite sex, post-pubertal genitals, and genital intercourse”, then the extremity of the deviation of a given perversion can be analyzed by contrasting with this defined baseline. iii [1975b, 23] Naturally, as the perversion is defined by sexual attitudes towards non-sexual objects, then the perversion is extremely deviant by this definition. By Nagel’s account, “narcissistic practices and intercourse with animals, infants, and inanimate objects lack the requisite ingredients of complete/natural sex.” iv [1969a, 5] By this definition also, then, sexual attitudes towards non-sexual objects must be perverse.
The clear outcome of these individuals coming to have reduced or no sexual interactions with other persons is one that poses a problem from the point of view of sexual behaviors as leading to reproduction, and presumably a more general suffering of mental health. Sociosexual isolation resulting from someone having reduced desire to engage or not engaging at all in sexual practices with other individuals is one of the harms that is resultant from this behavior. It is also notable that of the OS individuals studied, half suffered from autism spectrum disorders. It follows, then that mental health issues and sexual attitudes towards non-sexual objects are linked.v [2010b, 13]
Another sexual perversion frotteurism which is the practice of rubbing one’s genital area against a non-consenting person for sexual pleasure. vi [2014a, 1] The practice is commonly performed by men to women, but do occur with other combinations as well. vii [2014b, 1] The practice of frotteurism is distinguished between frotteuristic acts and the frotteuristic disorder. The former may occur in as many as 30% of all men. viii  Therefore, the reoccurrence factor is regarded as particularly significant on this issue. Due to the non-consensual aspect of the behavior, it is difficult to regard it as healthy sexual exploration, but the distinction between isolated and one-time acts of frotteurism, as opposed to a repeated behavior is also significant.
Due to the non-consensual characteristic of the behavior, it is inarguably deviant from normal sexual practices. On the other hand, frotteurism is also deviant in Ruddick’s definition of being deviant from “the standard aim.” ix [1975c, 23] This is so given the dual nature of frotteurism as being non-consensual on the part of the non-frotteur as well as the incompleteness of the act as it is non-reductive and is performed with a clothed partner. Finally, frotteurism can also be considered as a perversion due to the fact that it “goes against cultural norms” per Ruse. x [1995a, 113] Therefore, as the sexual practice is non-penetrative and thus incapable of leading to sexual reproduction and given its non-consensual nature it is indubitably deviant from normal sexual practices.
This particular perversion is regarded as harmful due to the non-consensual aspect of the practice. As opposed to the above-mentioned practice of having sexual attitudes towards non-sexual objects, the principle harm of frotteurism impacts not the frotteur, but rather the people with whom the person with the perversion has sexual interactions. By the definition of the perversion, frotteurism involves a non-consenting partner, and therefore, frotteurism leads to sexual assault and causes obvious distress to the non-consenting individuals who may be forced to sexually interact with the frotteurs. The harm of frotteurism is recognized by the APA, and the perversion is treated medically which is proof that it is indeed recognized as harmful. The treatment of the frotteuristic disorder comes in different forms but commonly involves cognitive behavioral therapy (CBT) coupled with a pharmacological course. Given the clear harm that the practice of frotteurism causes the non-consensual and possibly unaware partners of the frotteurs, and the fact that the behavior is recognized as a disorder and is treated as such by the APA, it is clear that frotteurism is harmful and can be considered to be a perversion from the harm perspective.
Transvestitism is a disorder with a long history that has been relatively pervasive throughout history, dating back to at least the Biblical times. xi  The distinction between sexual exploration involving cross-dressing and it being a sexual perversion is partially defined by the reoccurrence level of the practice. The extremity of the deviation comes in diverse forms – with some members only performing the act in the sense of dressing in clothing of the opposite sex, whereas others choose to be more committed to the practice, extending even to genital mutilation in an attempt to identify further with the opposite sex. xii  Therefore, a distinction can be made between sexual exploration involving dressing in the clothing of the opposite sex once, or a number of times, and a repeated occurrence of some other individuals who either do so regularly or even engage in genital mutilation as part of a ‘transition’.
Transvestitism has long been recognized as deviant by different scientists and psychologists, beginning with Magnus Hirschfeld who recognized that the practice of dressing in the clothing of the opposite sex was only an outward, basic manifestation of a deeper-rooted psychological disorder. xiii  This perspective is echoed by the DSM which defines transvestic fetishism as cross-dressing that occurs for erotic purposes for a period of at least six months and causing impairment. xiv  The definition of transvestitism is thus defined by differing materials and is consistently recognized as a disorder and/or a perversion. By Ruse’s definition, it is perverse as the disordered practice goes against cultural norms and unnatural. xv [1995b, 113] By Nagel’s definition as well, transvestitism is a sexual perversion as it is revealed “in conduct that expresses an unnatural sexual preference.” xvi [1969b, 5]
The harms presented by transvestitism, and its expression by the so-called ‘transgenderism’ practice which is the most recurrent and thus the most problematic and extremely deviant version of transvestitism are great and varied. Most notably, the suicide attempt rate amongst ‘transgender persons’ ranges from 32% to 50%. xvii  The suicide rate in the general Canadian population is 11.5 per 100 000 people, which means that the rate in this group 27 to 44x higher which is clearly an extremely significantly higher rate. Although certain groups claim that this risk of suicide is due to external factors rather than something that is inherently present in the individuals that are perverse in this way, the fact is that the reasons are truly largely internal. The issue is that discrimination is not a contributing factor of suicide for other groups who often report that they are discriminated against. As a matter of fact, whites commit suicide at a higher rate of suicide than black people. xviii  The highest rates of suicide occur with other members of the population who suffer from mental illnesses, and logically sufferers of this mental illness also suffer the same fate. The harm resultant from transvestitism, and the more extreme extension of the perversion referred to as ‘transgenderism’ is even more severe.
As can be seen from the exploration of a few examples of sexual perversions above, there is a wide variety of perversion that can be found and that vary in terms of their characteristics, and their resultant harm. It is notable that sexual exploration and sexual perversion need to be clearly distinguished. This is accomplished by looking at the reoccurrence of a given sexual behavior, the extremity of the deviation from the definition of normal sexual behavior, and finally the harm that results from the practice of a given perversion. With the examples given, the behaviors are all shown to be perverse on the criteria described, and despite the differences and disparities between the different behaviors they all share the traits that are described as traits belonging to a perversion. Although sexual attitudes towards non-sexual objects, frotteurism, transvestitism, and voyeurism are all certainly very different behaviors that manifest themselves differently and have different elements that make them perverse, by the given definitions. There is clearly a distinction between simple exploration and sexual perversion. It is normal human behavior to be curious and to explore that curiosity, but the line between simple exploration and perversity is a fine one. The prolificity of a behavior and the extent to which it replaces normal sexual behavior is an important distinction between the two, as minor deviations from typical sexual interaction are normal and occur commonly but major changes that replace, not simply deviate, normal sexual practice are prone to be more problematic. Finally and crucially, the harm resultant from perversions is a defining characteristic that most clearly distinguishes perversion from sexual exploration. The examples looked at all have a certain harm associated to them, to different extents. It can be stated that the more severe the associated harm, the more defined and severe a sexual perversion can be said to be. By looking critically at sexual behavior in this way, one can definitively define whether a given behavior can be said to be sexual exploration or something more serious and problematic, and consequently should be defined as a perversion.
i Ruddick, Sarah. "On Sexual Morality." Ed. James Rachels. Moral Problems. New York: Harper & Row, 1975. 23. Print.
ii Marsh, Amy. "Love Among the Objectum Sexuals." Electronic Journal of Human Sexuality, 2010. 13.
iii Ruddick, Sarah. "On Sexual Morality." Ed. James Rachels. Moral Problems. New York: Harper & Row, 1975. 23. Print.
iv Nagel, Thomas. "Sexual Perversion." The Journal of Philosophy 66.1 (1969): 5. Print.
v Marsh, Amy. "Love Among the Objectum Sexuals." Electronic Journal of Human Sexuality, 2010. 13.
vi LeVay, Simon. "Frotteurism." Frotteurism | SexInfo Online. SexInfo Online, 3 Apr. 2014. Web. 12 June 2017.
viii American Psychiatric Association, ed. (2013). "Frotteuristic Disorder 302.89 (F65.81)". Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition. American Psychiatric Publishing. pp. 693.
ix Ruddick, Sarah. "On Sexual Morality." Ed. James Rachels. Moral Problems. New York: Harper & Row, 1975. 23. Print.
x Ruse, Michael (1995). Is Homosexuality Bad Sexuality? In Robert M. Stewart (ed.), Philosophical Perspectives on Sex and Love. Oup Usa. pp. 113-124.
xi Aggrawal, Anil. "References to the Paraphilias and Sexual Crimes in the Bible." References to the Paraphilias and Sexual Crimes in the Bible - ScienceDirect. ScienceDirect, 07 June 2008. Web. 12 June 2017.
xii Hirschfeld, Magnus, and Max Tilke. Die Transvestiten : eine Untersuchung über den erotischen Verkleidungstrieb : mit umfangreichen casuistischen und historischen Material. Berlin: Pulvermacher, 1912. Print.
xiv "Diagnostic Criteria for 302.3 Transvestic Fetishism." Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) (2000). Print.
xv Ruse, Michael (1995). Is Homosexuality Bad Sexuality? In Robert M. Stewart (ed.), Philosophical Perspectives on Sex and Love. Oup Usa. pp. 113-124.
xvi Nagel, Thomas. "Sexual Perversion." The Journal of Philosophy 66.1 (1969): 5. Print.
xvii Virupaksha, H. G., Daliboyina Muralidhar, and Jayashree Ramakrishna. “Suicide and Suicidal Behavior among Transgender Persons.” Indian Journal of Psychological Medicine 38.6 (2016): 505–509. PMC. Web. 13 June 2017.
xviii Payne, Daniel. "The Transgender Suicide Rate Isn’t Due to Discrimination." The Federalist. The Federalist, 7 July 2016. Web. 12 June 2017.