Harmony holds the record for the longest a character has been in the Buffyverse on TV, being the only character to appear in both the Buffy unaired pilot and Angel's series finale. She also holds the record for longest wait to become a series regular, eight years, before becoming a regular right towards the end of Angel.

She is the only character to go from being a co-star (credited only at the end of an episode), through to guest-star and then ultimately starring as a regular.

Harmony has appeared more often as a vampire than as a human.

She, together with Buffy herself, is the only Buffyverse character to have two episodes named after her, "Disharmony" and "Harm's Way." The episodes named after Buffy are "Anne" (her middle name) and "Buffy vs. Dracula".

A running gag involving Harmony is her uncanny ability to escape from any given situation unharmed, despite her relatively feeble fighting skills. She is killed in "Graduation Day, Part Two", but returns the next season as a vampire. In the Buffy Season 5 episode "Real Me", Buffy slays every single one of Harmony's gang, but Harmony survives unscathed. In "Disharmony", she betrays Team Angel, but is allowed to leave unharmed by Cordelia. In the Angel finale "Not Fade Away", she betrays Angel for the second time, but manages to escape not only with her life, but with a recommendation from Angel.