Note, I'm putting this in the biology forum because there is no "sexology" forum. Also, I'm using this site (a science site) because I am not just looking for the reasons that you, personally, like lesbians, but rather, the scientific reason why they're so popular on a general level.
Think about it: Why do men enjoy homosexual porn of the opposite sex, but that same fetish is not near as widespread among women? How, exactly, does testosterone accomplish one thing, but estrogen does not accomplish the exact opposite?
Most guys give the reason of "twice the fun" for why they like lesbians, but that logic does not work with women liking gay men.
It is the job of scientists to inquire as to why lesbians are so popular among the sex they aren't attracted to, yet that does not work vice versa.
Why is that?