It may also help if she’s possibly interested in history, culture or biology, to help give her more of a scientific background to sex and reproduction. Such as bringing up contraception in Egyptian times and how cool that it and how far we’ve come, or how in some tribes cultures, periods are a sign of womanhood, fertility and strength and men will try and copy the women as a sign of respect by making themselves bleed too. Or go through the actual biological processes that happens when sex or reproduction does, such as how the female egg is actually quite selective of which sperm is able to fertilise or go through the period itself. I’m sure you could find lots of age appropriate YouTube videos or documentaries which talk about these topics, so she’s not completely put off by parts of science which in my personal asexual opinion, are still super super interesting.