Some info on Zhaan:

An 812-year-old 10th-level Pa'u (a priest), Zhaan was imprisoned for the murder of another Delvian priest - her lover - who she suspected was using his power to lead Delvia astray. Delvians are flora, not fauna, and therefore Zhaan, a plant-evolved being, has extreme reactions to solar energy, and has experienced photogasms -- intensely pleasurable experiences -- when exposed to solar flares. Additionally, Zhaan knows herbs and herbal medicine intimately, which often gives her the responsibility of doctor and healer aboard Moya.