She was an ancillary character in the TV series but I think she's a pretty interesting one for the simple reason that she would have a reason to return.

In the episode Terrible Tammy (you can find it on Youtube), she used Heathcliff's own personally imposed limitation to not beat up girls against him to beat him up. She could really lay the beat down on Heathcliff and most others. She at least seemed to be as tough and strong as Heathcliff. Thing is, she was a skinny girl. She was more quick and agile than strong and tough. In fact, I think she would have ranked along side my version of Hector at that time.

After Sonya beat up and drove off Tammy, the scolded cat left town only to be found by the ambitious, cunning, and manipulative vixen, Faye Wyld. The vixen taught the cat to access her feral instincts that house pets, even willful ones like Heathcliff, don't have. Tammy is a wild animal now and a heartless, vicious, fighter.

Because of her humiliating defeat at the paws of Sonya, Tammy wants the white cat's hide. But Faye has her hooks in Tammy and she is unwittingly little more than the vixen's henchgirl. Thus, Tammy hasn't gone on the warpath to murder Sonya. At least, not yet.

Her design in the show is simple and actually works pretty well for the attitude. There is really nothing to do to her. She's a fighter whose animal violence drive has been awakened so she tends to push her body harder more often thus she has become more buff from the skinny girl with attitude she was before.

Enjoy.