Pa'u Zotoh Zhaan is a Delvian, a blue, spiritual, humanoid plant species, and a Pa'u (priestess) in their religious order. Zhaan was imprisoned aboard Moya because she murdered her lover who was collaborating with the Peacekeepers, which she and her associates felt was a betrayal of Delvians. She has also been an anarchist, and like other trained Delvians, Zhaan has several empathic and telepathic abilities. She is also skilled in medicine and other related sciences. During her time aboard Moya, she is often seen making drugs and explosives in her workshop to assist her shipmates.

As a Pa'u, Zhaan's spiritual abilities significantly improve upon achieving a new level. When first introduced, Zhaan is a level nine Pa'u, with the ability to lessen the pain of others by taking some portion of it into herself. Later in the series, she gains a level, becoming a level ten Pa'u and gaining the ability to protect others from psychic attack with her own mind. In the episode "Bone to Be Wild" she shows that for short periods of time she can make herself invisible, although it is not stated whether or not this ability is only able to be exerted when surrounded by other foliage.

Towards the beginning of the third season, Zhaan saved the seemingly dead Aeryn Sun, and in the process became critically ill herself. While the crew are searching for a planet with the right conditions for Zhaan to heal, John Crichton diverts Moya to investigate a wormhole instead, where the Leviathan collides with another spacecraft. In order to save Moya and her crew, Zhaan sacrifices herself by piloting the other craft away before it is destroyed. In real life, Virginia Hey left the show because the character's extensive makeup was affecting the health of her kidneys. She still reappeared as Zhaan in two fourth-season episodes, "John Quixote" and "Unrealized Reality". Her voice was used in the Aeryn-focused episode "The Choice" from around the end of the third season as well.