Fetishistic disorder is characterized as a condition in which there is a persistent and repetitive use of or dependence on nonliving objects to reach sexual arousal. Only through use of this object or body part can the individual obtain sexual gratification. A diagnosis of fetishistic disorder is only used if there is accompanying personal distress or impairment in social, occupational, or other important areas of functioning as a result of the fetish.

Fetishistic disorder is a much more common occurrence in males, and the causes are not clearly known. Fetishism falls under the general category of paraphilic disorders, which refers to intense sexual attraction to any objects or people outside of genital stimulation with consenting adult partners.

The sexual acts of people with fetishistic disorder are characteristically focused exclusively on the fetish object or body part. Non-fetishists may at various times become aroused by a particular body part or an object and make it a part of their sexual interaction with another person, but they do not fixate on it.

Behavioral learning models suggest that a child who is the victim or observer of inappropriate sexual behaviors learns to imitate and is later reinforced for the behavior. Compensation models suggest that these individuals are deprived of normal social sexual contacts and thus seek gratification through less socially acceptable means. In the far more common cases involving males, the patterns suggest that causes stem from doubts about ones own masculinity, potency, and a fear of rejection and humiliation. By his fetishistic practices and the mastery over an inanimate object, the individual may safeguard himself and also compensate for some of his feelings of inadequacy.

https://www.psychologytoday.com/conditions/fetishistic-disorder