Well I guess it's about time someone proposed these two goofballs lol.
What's the Work?
Chainsaw Man is a manga series created by Tatsumi Fujimoto in late 2018. It is pubilished in the magazine Weekly Shonen Jump.
Who are the Characters?
Denji is the overall protagonist of Chainsaw Man, being a hybrid of human and devil which allows him to turn into the titular Chainsaw Man.
Power is a major character of Chainsaw Man, serving as one of the two deuteragonists for the Part 1 of the manga.
What Makes Them Shonen Heroes?
Denji:
Heroic/Honorable: While he initially does it for mostly selfish and superficial reasons, Denji has protected Tokyo from several devils, and as the manga goes on, he becomes more mature and kind with his actions.
Reckless: Denji doesn't usually think before acting, as a result he oftens just jumps head first into danger .
Energetic: He's usually very loud and abrasive, although as the story progresses this slowly dies down.
Stubborn: Denji refuses to listen to Aki when he tells him to leave the Security Bureau.
Pursues a Big-End Goal: His main goal is to raise the popularity of the Chainsaw Man so he can finally get laid. He also has the side goal of wanting to give Nayuta a normal childhood he couldn't have.
Hard-Working: Denji works hard to keep his job so he can keep living a "normal life", and also to provide a normal childhood to Nayuta.
Unintelligent: A much more tragic example, Denji never had any sort of access to education during his childhood, as a result he grew up as a very uneducated individual that lacks basic manners, and is almost illiterate.
Possesses Plot Armor: Thanks to being immortal, Denji is able to survive any fatal injury. He also gets revived by Pochita/The Chainsaw Devil at the beginning of the story, allowing him to become Chainsaw Man.
Spiky Hair: Denji has rather spiky hair, although unlike most examples it's likely due to him not treating his hair well.
Short-Tempered: He tends to lose his head pretty quickly when frustrated, which leads to his more berserk moments.
Has Rivals/Mentors: He initially has a brief rivalry with Aki upon joining the Security Bureau (which completely dies down after both become friends), and later has a much more straightforward one with the Katana Man. Denji was also trained to become a better fighter by Kishibe.
Big Eater: Denji really enjoys eating thanks to not having much food to eat while growing up, and will usually eat everything that is edible with pretty much no complaints.
Has an Idol: Denji initially worships Makima, but grows out of it after learning her true colours.
Mischievous: He enjoys pranking Aki during his free time.
Rebellious: After his experiences with Makima, Denji becomes a lot more reluctant when it comes to receiving orders, and typically hates being told what to do by men.
Tragic Past: His father was an abusive alcoholic with a huge debt to the Yakuza, and after his death, Denji ended up inheriting his debt, as a result he grew up poor with no parental figure, never went to school and surrounded by the Yakuza.
Is a Blood Knight: Denji can be downright bloodthirsty when killing devils, with his fight with the Eternity Devil being the most notable example.
Power
Heroic/Honorable: Being a part of the Security Bureau, Power has helped to stop many devil threats in Tokyo, with her most notable act being sacrificing herself so Denji could defeat Makima.
Reckless: Much like Denji, she also doesn't typically thinks before acting, and ends up jumping head first on danger with no hesitation.
Energetic: She's VERY loud, and even manages to beat Denji in this aspect as she's twice as hyperactive as him.
Pursues a Big-End Goal: Power’s goal is to win a Nobel Prize and become Prime Minister. She also wants to protect her cat, Meowzy, at any cost.
Unintelligent: Power is very scatterbrained and ditzy, and much like Denji she lacks basic manners.
Believes in the Power of Friendship: Power begins to really value her friendship with Denji, to the point she sacrifices herself for him, playing a key role in Makima's defeat.
Short-Tempered: She gets frustrated really quickly when things don't go her way.
Has Mentors: Much like Denji, she was trained by Kishibe to become a better fighter.
Big Eater/Drinker: Power really loves eating anything that isn't vegetables, and also enjoys drinking blood to the point she goes overboard with it.
Mischievous: Alongside Denji, she enjoys pranking Aki on their free time. She also has no qualms about pranking Denji himself.
Is a Blood Knight: In the most literal way possible, Power really enjoys drinking the blood of her enemies.
Veredict?
Pretty easy yes to both. Denji is a very big deconstruction of the Shonen Hero archetype, and Power herself also manages to fit it pretty well.
