Triana Orpheus first appeared in The Venture Bros. episode “Eeney, Meeney, Miney… Magic!” (Season 1, 2004), voiced by Lisa Hammer. She is the goth, purple-haired teenage daughter of the theatrical necromancer Dr. Byron Orpheus and his ex-wife Tatyana, and she moves into a wing of the Venture Compound with her father after their marriage collapses. Orpheus had neglected her as a child while chasing occult mastery, a history that left her dry, impatient, and far more grounded than the super-scientists and villains around her. Dean Venture is instantly smitten; she finds him odd but “kind of cute,” and when Dean, Hank, and Brock are trapped in Dr. Venture’s Joy Can, the sound of her voice is what lets Dean’s idea of true love open the door.

Through the early seasons she is a recurring neighbor rather than a lead: she attends school off the compound, keeps friends such as Kim, endures a disastrous double date arranged so Orpheus can cover the rent (“Victor. Echo. November.”), and discovers that her closet hides a gateway to the Necropolis because her father’s mentor, The Master, has been living in it. Orpheus had been wiping her memory after every encounter with that entity, which is why she had been afraid of the closet her whole life and tended to wear the same clothes. She has inherited raw magical talent from both parents but has never been trained.

Her major turn comes in the Season 4 episode “The Better Man.” The Master appears to her as an older, neurotic version of Dean—a glimpse of a future as Mrs. Venture that horrifies her—and tells her she will become a great sorceress only if she leaves the compound, trains with her mother and stepfather the Outrider, and “sets Dean free.” She does all three: she gets Orpheus’s blessing, ends things with Dean as kindly as the show allows, and gives him a goodbye kiss. When Dean later asks her to prom in “Operation P.R.O.M.,” he learns she is already seeing someone named Raven. After that she largely exits the boys’ orbit, last seen pursuing the occult life the series had been pointing her toward from the moment she walked onto the compound.