Gsptlsnz was a being from the Land of Zrff in the Fifth Dimension. She appeared to be romantically involved with Mr. Mxyzptlk and possessed the same powers as her lover. Gsptlsnz didn't have any particular ambitions, it appeared, other than to love Mr. Mxyzptlk and get attention from him.
While Mr. Mxyzptlk was known for being wild and obnoxiously crazy, Gsptlsnz seemed to be the exact opposite. Laid-back and largely indifferent to the idea of annoying mortals, she seemed completely unconcerned when Mxyzptlk became obsessed with defeating Superman. Yet despite her indifferent nature, Gsptlsnz cared a great deal for her husband and simply desired attention from him. She would often change her clothing in order to attract Mr. Mxyzptlk. In the end, Superman was able to permanently banish Mr. Mxyzptlk from Earth, Gsptlsnz finally got the attention she wanted, even if it was a bit divided.
Unfortunately, Mr. Mxyzptlk couldn't stand leaving Superman unannoyed, so he tricked Bizarro into attacking him. Gsptlsnz tried to warn him that the leaders of their dimension would be furious, but Mr. Mxyzptlk wouldn't listen. Sure enough, a tribunal called Mr. Mxyzptlk to account for his actions. Gsptlsnz tried to argue leniency for him, which made him happy but the tribunal turned her into a palm tree, much to her husband's sadness. Once Mr. Mxyzptlk was sentenced to ninety days on Earth, Gsptlsnz was restored to normal.