Irwin is a nerd who desperately aspires to be cool and frequently ends sentences with "yo". He has an unhealthy crush on Mandy (ever since Billy possessed Mandy in Get Out of My Head! and said to him, "You are such a cutie!"), and longs to gain her affection, often stalking her. He frequently fails in both those goals, typically embarrassing himself and getting beat up by her. Irwin might be one of Billy's closest friends, but is often forgotten in dangerous situations, as well as being used as bait.
Irwin's mother is a mummy, which make Irwin 1/2 mummy, and Irwin's father is 1/2 vampire, (Irwin's paternal grandfather is Dracula,) which makes Irwin 1/4 vampire; however, in Underfist he is referred to as half vampire half mummy.
Because of Billy putting his life in danger almost every day, it's natural for him to have a cowardly personality. It is possible because of his mostly supernatural heritage that he was born evil. However his father Dick taught him about being a good person (which is fortunate since he would have become a male version of Mandy: selfish, cruel, merciless and so on). But like his chances of getting a date with his dream girl, the chances of his evil personality are slim to none. Irwin has tried to make Mandy like him.
Occasionally, Irwin goes through occasional power trips; during these instances of egomania and megalomania, Irwin plots to make Mandy his queen, which she of course refuses. Two of these occasions are King Tooten Pooten and Scythe For Sale. In the former, he becomes a pharaoh and brainwashes all of Endsville into building him a pyramid, not caring whether or not they remain hypnotized for the rest of their lives. In the latter, he uses Grim’s scythe to brainwash Mandy into falling in love with him and starts to cause trouble all over the town. He then nearly makes Mandy his wife by forcing her into marriage.
Abilities and Skills
As one-quarter vampire, and half mummy Irwin is gifted with incredible supernatural abilities which only develop in Underfist: Halloween Bash.
- Superhuman Strength: He was able to lift Hoss by his hair, even in bat form, and throw him against a metal wall hard enough to dent it. He was also able to hold back a giant monster with just his claws.
- Shapeshifting: He can transform into a bat and other animals at will.
- Flight: Even when not in his bat form he can lift himself off the ground and fly at an unknown speed.
- Bandage Control: He can control the bandages wrapping his body with his mind at will. They are capable of lifting objects up to an undetermined weight. This ability was inherited from his mummy mother.
- Dark Energy Control: Irwin can fire blasts of dark energy from his hands, or focus the dark energy into huge orbs and spheres of dark power.
- He seems to wear diapers and cannot control his incontinence, though this is only for short lines such as "Good thing I wore diapers today," after Billy almost destroys the school bus he is riding on.
- This gag is also referenced in the "Hate in an Elevator" short, where Tanya states that she has to cover her furniture in plastic when Irwin comes over.
- When his vampire-mummy powers start showing, Irwin's reflection can't be seen because vampires don't have reflections.
- Irwin is voiced by Vanessa Marshall, who is also known for voicing many DC comics females such as Black Canary in Injustice 2.
- Vanessa Marshall has stated that Irwin is one of her favorite roles, and has noted that she (like Irwin) is a nerd.
- Irwin was transformed into a werewolf in an early episode, back when the show was part of Grim & Evil.
- It's been shown that Irwin was evil as an infant; presumably, this could have been due to his monster heritage.
- This is further hinted in Underfist, where Bun-Bun believes that Irwin should join the side of evil because he's a mummy-vampire.
- Despite being a vampire, he doesn't mind the sun; this is probably because he's 1/4 human thanks to Tanya.
- Additionally, his grandfather Dracula has no problem traveling in broad daylight (save for his first appearance, where he did start burning in the sunlight).
- This may be due to the fact in the book Dracula, Dracula was still able to walk in the sun, but simply had weakened powers.
- Irwin has been described as "1/2 vampire, 1/2 mummy, and 22/7 nerd"; while he's technically 1/4 vampire, 1/4 human, and 1/2 mummy, it should be noted that 22/7 is the fractional approximation for pi (π). This statement is to help accentuate that he's a nerd, providing a "Genius Bonus" by using a fact that only a "nerd" would understand.
- Irwin seems to have become a more popular side character, ascending to protagonist status later on and being the definitive protagonist of Underfist. Additionally, he has made quite a few appearances in Cartoon Network crossover media.
- Irwin's family (on his father's side) seems to have a an inherited verbal tic: Irwin often says "yo" after his sentences, his father refers to people using the word "dude", and his grandmother tends to refer to loved ones using "baby".
- A joke that's been used at least twice is Irwin and his father exchanging dialogue consisting only of "yo" and "dude", respectively.
- It can be concluded that Irwin's crush on Mandy started in the episode "Get Out of My Head!"; when Billy (in Mandy's mind) encounters Irwin, he is initially afraid of Mandy. However, when Billy-in-Mandy's-mind flirts with Irwin, Irwin becomes somewhat shy and shows some attraction to Mandy. This may have been what triggered his crush on her.
- In the Underfist special, right before his powers developed, Irwin's eyes glowed red. While this is a very commonly used technique in fiction, this trait coincidentally parallels Bram Stoker's Dracula; in the book, Dracula's eyes are revealed to be blue, and that they turn red when angered. This makes sense not only because Irwin's grandfather is Dracula, but also because Dracula's eyes are usually blue.
- Despite typically being regarded as only slightly less stupid than Billy, Irwin's shown to have some intelligence; not only is he definitely smarter than Billy, but he has been regarded as a "math nerd" (among other monikers) by Mindy; he corrected Bun-Bun on his grammar in Underfist (noting that "once and for all" and "permanently" mean pretty much the same thing); and, in the video game, he accurately clarifies that the Brain Eating Meteor is technically a Brain Eating Meteorite, as it had already made contact with the Earth's surface.
- Despite borrowing from hip-hop culture in some situations, Irwin explicitly states in "Goodbling and the Hip-Hop-Opatomus" that he's not allowed to listen to hip-hop music. Additionally, Irwin's attempts at emulating the hip-hop style stem from and are limited mostly to his attempts at being cool.
- In Underfist: Halloween Bash, one of the names that Hoss accidentally calls Irwin is "Urkel". This is a reference to Family Matters character Steve Urkel, as well as Irwin's vague resemblance to the character.
- While Irwin's species has only been referred to as a "mummy-vampire" or "vampire-mummy", some concept art for the unmade Underfist series refers to Irwin as a "mumpire", a portmanteau of the two words. While the term was never officially used in-universe, some fans have taken a liking to calling Irwin a mumpire.