Seven Sins

RetroSpecter

The title character and first opponent of the mod. He embodies the sin of Wrath.

Evil Sounds Deep: Retro's voice samples and his snarl of "ENOUGH" during "Satisfracture." Berserker Retro's voice is even deeper.
Friendly Enemy: Averted in the Canon Cutscenes, but played straight in some of the alternative cutscenes as they have Retro act surprisingly nicer than usual depending on who replaces BF and who replaces GF, with the Berserker Retro triggers either being caused by him wanting to make things more interesting, him embarrassed with Saku and just skipping to phase 2 before she says anything else, or him being a Tsundere around Ace.
Hair-Trigger Temper: As expected from the Sin of Wrath, Retro is already pissed from the start, and goes absolutely berserk after just one song.
Magic Pants: Retro's clothes stay completely intact (aside from the crystals ripping through) after transforming into Berserker Retro. Justified, as apparently Izzurius, the Sin of Pride, specially made them to be extra stretchy and resist acid burns.
One-Winged Angel: After losing the first song, Retro becomes Berserker Retro, also known as Zerktro.
Prehensile Tail: Retro's tail ends with a clawed hand that he uses to hold his microphone.
Tsundere: He acts like this around Fun Sized Ace if you're playing as Ace and use Minus GF. This trope even causes his Berserker Retro Transformation.

Sakuroma

The second opponent of the mod. She embodies the sin of Lust.

All Women Are Lustful: Saku really takes an interest in Boyfriend and makes it clear what her desires are, outright suggesting a foursome in one exchange.
Extreme Omnisexual: Being the physical embodiment of Lust, it's no surprise that Sakuroma wants to get freaky with anybody of any shape, form, or gender. Even a clone of herself.
Ms. Fanservice: Sakuroma to a T. Justified, since she is the Sin of Lust. In addition to her design, provocitive poses and personality, seductive laugh, and bounciness, her Minus counterpart is wearing a skimpy cheerleader outfit.
Screw Yourself: Sakuroma proposes having a foursome with Boyfriend, Girlfriend, and even a clone of herself. In the alternate version of Fuzzy Feeling with Saku facing a fun-sized Saku and a Saku on the stereo, all three take interest in having fun with the microphone.
Shameless Fanservice Girl: Izzurius' reference sheet reveals that Sakuroma does have clothes, she just chooses not to wear them (much to Izzurius' annoyance).
Statuesque Stunner: Sakuroma applies, due to being confirmed prior to the mod's release to be 9'6'' and representing the sin of Lust.
The Tease: Sakuroma loves to flirt with everyone and teases Retro in particular cause she loves how tongue-tied he gets when he tries to maintain his tough guy look.

Izzurius

Creepy Crows: Izzurius, the Sin of Pride, is described as a Plague Crow, and he apparently made Retro's clothing.

Insatian

Extreme Omnivore: Naturally as the Sin of Gluttony, Insatian will eat anything and everything, from rocks to Izzurius' potions to even her own species.
Gruesome Goat: She’s easily the most demonic looking of the Sins, and has goat theme in her design.
Sizeshifter: Insatian's size varies depending on how much she has eaten, from being 5'4'' at her smallest and being an even 20' at her biggest, though if she doesn't eat she will shrink back down.

Hivemine

Bee Afraid: Along with her bee theming, Hivemine also has hundreds of bee minions, 3 named ones being Barry, Larry, and Terry.
Fun with Acronyms: Not Hivemine but rather her three named bee minions, Barry, Larry and Terry are collectively called The BLTs.
Shed Armor, Gain Speed: Hivemine's Hiveless form serves as this, sacrificing storage capacity for better speed and agility.

Atrocean

Green-Eyed Monster: He is the Sin of Envy after all, and believes he deserves the title of Wrath more than Retro. He’s also literally a green eyed monster.
Soul Eater: Consumes souls trying to pass into the underworld using the souls attached to him as lures.

Dozirc

Colour-Coded Emotions: His core changes color based on his mood.
Gentle Giant: He's the largest of the Sins, even bigger than Berserker Retro. That said, he's also the most laid back of the group, being the Sin of Sloth, and hates accidentally hurting small creatures.

Other Characters

Kamex

Retro's boyfriend, in-universe and out.

One-Winged Angel: Much like Retro, Kamex has one of these. He calls the form Iceolation.
Opposites Attract: He's a calm and collected ice dragon, Retro is the sin of Wrath, and yet they're happily dating.

Metro

Jerk Jock: He tends to be pretty standoffish, and he will throw his football at Minus Boyfriend's netherregions whenever he wins or whenever he gets fed up with Minus Boyfriend correcting his English.
Graceful Loser: While he gives Boyfriend crap for most of the week, he lets Boyfriend know he had fun after losing to him on Overtime.
Malaproper: Metro has a habit of saying words incorrectly. Minus Boyfriend learns the hard way that correcting him too much will end badly.

Maku

Innocent Fanservice Girl: Unlike Sakuroma, Maku doesn't deliberately flaunt her figure but ends up doing it regardless due to being a cheerleader.
Pom-Pom Girl: Maku provides support for her team, and while she has the fanservice body like that of her regular counterpart, she is a lot more shy. She also has pom-poms which she harmlessly throws at Boyfriend when he loses.
You Are Better Than You Think You Are: When Metro asks her to take over for him, she is reluctant and says she can't sing. After one song, everybody assures her that she was amazing.

Mizzy

Minsatian

Hinus

Matreus

Mozy