Hello new not!mother...

While Rin herself isn't exactly the science you're probably looking for, her magecraft does involve a bit of it so they might have that mutual interest. I think a lot of their early cr will just involve... tolerating each other.

Unlike the way she is with Kirei, she'll probably approach Danger sweetly with a more mature attitude. She's just different all right! If she needs help with anything girly though... :D