Koshka is a bit of a hub character on the Fold, she interacts with a lot of the storylines and other heroes simply because she is too curious and wild to stay in one place for too long.
She was orphaned as a baby in a war between Grangors (Glaive’s people) and humans. A Grangor found her and raised her, teaching her how to hunt, leap, and hide. The Grangors also made the metal claws that she uses because her human nails were too weak. However, Koshka soon became curious about the outside world and left her home.
Koshka is unfamiliar with normal human items and behavior, inadvertedly threatening Petal, Krul, and Adagio with a scout trap for example. We know Koshka is somewhat familiar with Celeste, having observed her enough to mimic Celeste’s behavior. Koshka is about as far from Celeste as you can get though, where Celeste is shy and more reserved Koshka is in your face and ready to play!
She loves minions, spoiling them with minion candies and other goodies. However, she also showed her sweet side with Ozo, playing at the Red Lantern Festival with him in the Undersprawl; the same place Ringo and Glaive meet. She even had a run-in with SAW when he was hired to kill her, although he never managed to do so.
It wouldn’t be too far off to say she’s the center of the Vainglory universe, but really she’s just exploring and playing with everyone she comes across!