Frankly, the rationalization could be as benign as "the bedroom is the only harmless put to experiment with these things, due to the fact I can just move it off as a kink", but I guess this warrants a entire DSM entry. This was renamed to "Gender Dysphoria" in the 2013 DSM 5 since "Gender Identity Disorder" indicates the ailment is the gender id, not the dysphoria triggered from an incongruent one.