Alicia

Alicia is a female kangaroo and mail carrier for the O-Town Post Office whom Rocko becomes attracted to in the episode, "S.W.A.K." Rocko makes many attempts to tell her that he has a crush on her but when he finally builds up the courage and presents a love letter to her, Alicia is revealed to be out sick for the day with Heffer substituting her route. After Heffer mentions the possibility of Wallace, who is supposedly Alicia's boyfriend, not taking kindly to the love letter, Rocko attempts to retrieve his letter before it falls into the hands of Wallace. His attempts fail however and Heffer successfully delivers the letter to Wallace, who mistakes the letter as intended for Heffer. Despite this, Alicia apparently receives the letter beforehand and writes a response to Rocko, mentioning that she finds Heffer 'cute'. Rocko is heartbroken while Heffer becomes excited and leaves before Alicia arrives and reveals to Rocko that her letter was simply a prank to Heffer. It's implied that Alicia has a crush on Rocko.