@ Mr. Spak
I dunno, I think it's sort of fundie? It's basically saying "No, the asexual people can't used this adjective, it belongs to the gays," which I think qualifies as gay fundie.
If a Christian tried to claim their religion basically owned a word, especially an innocuous one as that seen here, I don't think anyone here would have a problem pointing and laughing at the crazy.
Edit:
@ Skidie
I only kind of got my shit together and started figuring myself in the past couple years, and I can't purport to speak for all asexual people, but I can give you my perspective, I guess.
I know I get really uncomfortable when conversations get sexual (even fairly tame, workplce-acceptable levels of sexual), and I don't like being forced into a sexual mindset. I'm not a sexual being and any attempt to make me one (including comments or jokes about me banging anyone) put me off.
A lot of asexual people have a libido, because hormones are still a thing, even though they don't experience sexual attraction/have any real desire to do the deed. Many people who are asexual still have sex (because they have an SO who is sexual, for example). Some are capable of enjoying sex when they do have it, some are utterly repulsed by the whole affair.
A good rule of thumb (in my opinion) is that if you wouldn't say it to/ask it of a homosexual person, don't do it to an asexual person, either. (i.e. "You just haven't found the right X yet.")
Another good point to keep in mind is that you can find someone attractive, without finding them *sexually* attractive. There's lot of girls who I find attractive, and if I were in a commited relationship with one I'd be more than willing to sleep with them, but saying "I think you're pretty and would have sex with you if you wanted" isn't the same thing as "I think you're pretty, and want to have sex with you." Erasure of identity is real, and it sucks.
I think simple acknowledgement that she's a person, this is how she is, and she can do things (find someone pretty/handsome, have sex with someone she cares about if he so chooses, etc.) without it invalidating her would go a long way; it does for me. If she tries to steer a conversation away from sex, maybe go with her on that, so she doesn't get steamrolled by others? I don't know how bold your sister is, but I'm a little bitch and I'll suffer in silence through an uncomfortable conversation.
There's probably way better resources than myself but that's my two cents, for what it's worth.
Edit 2: I have a really closecfriend, he was the first person I came out to, and he makes jokes sometimes abiut me being an asexual space potato. They're not at my expense, or mean, they're just... good-natured jokes like all the others we make at each other. I like them, because they're normalizing. Making it a natural part of your normal discourse is really freeing, at least I think so.
