Anything That Moves: She flirts with practically everyone, single or married, mare or stallion, stranger or her best friend.
Bi the Way: Her attraction to Arcanus is clear, but she also hints that she'd take a shot at Stella herself if no one beats her to it.
Chivalrous Pervert: She technically solicits a callmare (that she finds very attractive) and opts to do nothing with her, refusing to take advantage of a poor single mother. She also states that, despite her libido, it's actually been awhile since she last got laid.
Glory Days: She used to be quite an athlete, to the point of having the fastest gallop in the kingdom and being known as the Red Mare (almost certainly a reference to Red Hare). However, she insists she's "outgrown" such silly games and intends to pursue a career in academics.
Playing with Fire: Hinted to be her special talent, and a powerful one at that. The fire she lights is almost strong enough to melt a fireplace poker.
Sophisticated as Hell: Being a Victorian-esque upper-middle class lady of taste doesn't preclude her from using such language as "laying it on thick," "bingo!" and referring to socialization as "mingling."
Love at First Sight: Possibly. Arcanus' feelings were far more blatant, but the fact remains they were married by the next chapter.