Classical allusions[]
It is possible that she corresponds to Calliope, muse of epic poetry. This is supported by the fact that she possessed van Rijn's notes; Calliope was the leader of the muses in Greek mythology. On the other hand, as an astrologer, Urania is also a possibility. Possession of the notes may simply be due to her having a place to secret them.
Extended "family"[]
Given that Anevka/"Lunevka" is (at the least) based on Tinka's design, she may be considered a kind of distant cousin as well.
Her Undying Majesty may be a sister of this sort, if this speculation turns out to be correct.