Abnormal isn't a good word to use here since it connotates an undesirable condition, implying a need for correction.
Atypical, non-standard, or unconventional are more neutral in tone, so given your desire for a non-subjective word I'd recommend these instead.
Meanwhile, my original comment was more intended as commentary on the pervasiveness of leering.
Of course, it's an unprovable conjecture - but it sure would explain a few things.
If something falls out of the center of the normal distribution, it's by definition abnormal. Once again, that doesn't make it bad per se. But trying to police perfectly good words just makes people become more antagonizing to the position you want to defend.
Abnormal is a completely unscientific and immoral word to use in the context of consentual sexual behaviors for it is factually wrong (see the distribution of homosexual or bisexual behaviors in mammal species including humans), and also invoking a moral presciptive by declaration "what should be normal" via telling other people what "is not normal".
You fall into the same trap ("non-standard", "atypical"); you just stepped on the euphemism treadmill.