Millie is a very lively and cheerful individual. Often with a smile on her face and rarely standing still, she is a clear extrovert and is not afraid to speak her mind. This is regardless to whether it's expressing her excitement or flipping off a co-worker. As the bruiser for I.M.P and as an assassin, she is shown to enjoy her job. Her meek exterior appearance belies a tough and very violent skillset. This is highlighted during a conversation Millie once had with her mother and sister. According to Moxxie, she is aggressive in "the sack" as well as her job. In "Murder Family", she appeared to be very unsympathetic about killing a possibly innocent target, only caring if it was what their client wants, showcasing her dedication to her work, and her ruthlessness. However, in "Bad Reputation," in a flashback, she was genuinely horrified at innocent people get killed for no reason

Sallie May is a rather tall imp, roughly the same height as Blitzo, with light maroon skin and a pair of serrated, black-and-white-striped horns atop her head. Her eyes sport yellow sclera, slit-like pupils, and long eyelashes protruding from them, with a single white scar over her right eye and on her notched eyebrow. Her charcoal-colored hair is long with white-colored roots, and is usually tied back into a ponytail by a brown hair tie with messy bangs that covers her left eye. Tied around the back of her head is a red bandana with holes. Her attire consists of a sleeveless, black turtleneck crop-top with various tears at the bottom, heavily ripped black leggings under a set of gray-beige short-shorts held by a black belt with an oval-shaped dark gray buckle, and matching-colored cowboy ankle boots. And is Sallie May is shown to be just as cheerful and violent as her sister. She is also shown to be relatively snarky, most notably towards Moxxie. According to herself, Sallie May is more careful to hide the bodies of people she's killed, unlike Millie. She also appears to be a bit more laid-back than Millie, as shown from the way she talks. In "Hell's Belles", she reveals that she misses her sister and is sad that she never visits home often because of her life in Imp City, making her have to help her parents out with everything in Millie's place. She slowly begins to overcome this when Millie says that she will never be too busy for her sister and that, since their brothers are older and able to help their parents at the ranch, she can visit too.

Joe, like his wife, is fond of war and violence; upon meeting Blitzo, Joe and his wife took a liking to him due to his compliment on Millie being tough and his name reminding them of war. Similar to his wife, Joe was not very fond of Moxxie given his diminutive stature and preference for ranged weapons. By the end of the episode, after Moxxie stood up to Joe and his wife after they chastised Millie, he appeared to express some grudging respect for Moxxie as conveyed via a nod.

Lin bears a striking resemblance to her oldest daughter, Millie, with the exception of having numerous white spot-markings all over her body, short chin-length graying-hair in a bob cut, and burgundy cloven hooves. Her body type is voluptuous with prominently large breasts, wide hips, and thick thighs.

Cassity is a curvy imp with red skin, large eyes with yellow sclera, dark charcoal hair in a scruffy bob cut style with bangs that cover her forehead, and swirled white-striped black horns. She has a black tip on her long tail. She wears a light green V-neck shirt with torned sleeves, tight high-waist black pants with a green snake print on the right side, and knee-high hot pink cowboy boots Cassity is loud, exaggerated, and envious person. From when she knew Millie from their childhood, she always noted that Millie had something she didn't. Cassity believes she knows better, expecting her teammates to listen to her plans that only involves her own benefit but not the safety of other demons. Deep down, Cassity is insecure about herself and compares herself to

Willow is a cheery and outgoing imp who greets everyone she meets with a bright smile. Having a talkative nature, she makes sure everyone around her is welcome and that they have a good time whenever they visit her hometown. Like the rest of imps native to Wrath, she loves brawling and engaging in fights, especially at the Wackford Hoedown where she gets to sing, dance, and roughhouse with her family and friends, as well as her girlfriend. However, contrary to her sin, she doesn’t possess the more brutish, hostile and unforgiving nature her people has, as when Millie decides to walk away when she had every power to kill Cassity, she and Sallie cheer for her as opposed to the audience (including Millie’s family) booing at her.

Winston is an average sized imp, with enormous curling horns, and a short red-and-white striped tail with a spiral at the end. His eyes are pure yellow with no pupils. He wears a white cowboy hat with a red stripe and a black W symbol on his head, a white jacket with black sleeve trims and a red collar over a white shirt, black pants, and black boots with red toes resembling those worn by Blitzo.