Kula Diamond is a product of the NEST Syndicate. She was created to be the anti-K'. Where as K' controls fire Kula manipulates Ice.
Episode 3: In the Dark
Kula's part in the story is extremely small. She and Whip were on the train that Maxima and K' jump on to after their encounter with the Ikkari Warriors (Ralf, Clark and Leona). Kula is very worried about K' after finding him lying on the subway car floor. K' is just upset with Maxima but is all right.
As the Anti-K' Kula fights in a manner similar to K'. Unlike him she is a Cryokinetic (Formation and Manipulation of Ice) and even fights in Ice Skates (which are sharp enough to cut her opponents).