What I think of when I think about "loves Corwin, knows about Asgard and Diqiu, whimsical, creative, and not jealous", my mind immediately jumps to Anthy. I don't know if she knows Chinese or is an artist, but both of those could be outsourced.

Aside from all the other things, she actively wants Utena... and Korra... to become canon. Also, anyone else would have written Anthy Loves Corwin at some point because that love is also blatantly obvious; however, she doesn't need to, because she and Corwin already know it. The rest of the stories may be camouflage, or they may be just because Anthy is in fact a little bit evil.