That mean's when u like only Alex. And you wanna fuck them. (her/him/them)
My friend: anyway what is your sexuality?
Me: Oh, I'm Alexsexual.
My friend: huh, what?
Me:y'know i just rly wanna fuck them, they're so hot My friend:oh okay
Someone who is attracted to buttholes. They can be either male or female buttholes. It is used in the same way you would use the word bisexual or homosexual.