@MangaField
The WHO is useless as a measurement of how many people are messed up. Play to much video games? Disorder. Have gender dysphoria? No no no, that's "normal" nowadays.
Having a foot fetish has a neurological cause, because the area of your brain used for recognition of body parts has feet quite close to sexual organs and for some people they overlap. Foot fetishists have a "neurological disorder". Not like it'll be recognized by the WHO though, as it has no negative connotations. Flavor is completely correct in his statement that everyone is messed up in some way, but the definition of "messed up" is subjective.