Board Thread:General Discussion/@comment-27324545-20160105135410/@comment-36174925-20181231011132

Rainbow Birdie Frisk doesn't have a set gender. We can choose whether Frisk is a boy or girl (in my opinion a boy) plus, you can't tell if Alphys is a boy or girl at first, (she is a girl) but she's a lot older than Frisk.

And even if somebody is younger than 8, you can still tell if they're boy or girl.

I'm out.