Bodhi first appears when you have gathered 15,000 gold towards the rescue of Imoen. You meet her at night in the Athkatla graveyard, where she offers you an alternate path to Spellhold; in an unmodded game, you must side with her against the Shadow Thieves, or with the Shadow Thieves against her. Regardless of which side you choose (siding with Bodhi is generally known to be the greater evil by far), by the time you reach Spellhold she will be your enemy. Towards the end of the game, you will be hunting her fully as much as you are hunting Irenicus.
By the time you encounter her, Bodhi is the leader of a group of vampires in Athkatla. She is later revealed to be a former elf, exiled from Suldanessellar for participating in the crimes of her brother, Joneleth
. Both she and her brother were stripped of their elven spirits in punishment for what they had done. Bodhi embraced vampirism in an attempt to counteract the loss, while her brother devoted his arcane skills to claiming new souls for them both.
Bodhi comes across as sultry, cruel, and colder than ice. She seems to enjoy toying with the game's protagonist, whether you are siding with her or not, and the missions she will send you on are often outright assassinations. Several of your companions will voice their distrust of her when you first meet, and many of the good-aligned characters will leave your group forever should you choose her over the Shadow Thieves.