Character Analysis - Relation to plot
Kazuma at the age of 16 has very few if any redeemable character traits, and that's what makes him so god damn hilarious, it's because he wants to be a good person - Or at least viewed as one. Often at times being no stranger to milking his pride and small accomplishments to peers, and lying all too often about the extent of his "heroic" feats. Though there's a duality between him & characters such as Aqua who expose and poke fun at each other and who they really are, and as a result he often times abandons his pride to become something much worse - Often showcasing Kazuma's warped and perverted side, letting the cat out of the bag so to speak. Throughout his adventures we see how hilariously greedy and selfish he can be and how needy and pathetic characters like Aqua can be. Often times having to facilitate a balance between his party members lack of any logic and overspecialization in a particular skill or lack thereof, by learning more basic and core skills one would need to normally go about in combat.
Kazuma at the age of 16 has very few if any redeemable character traits, and that's what makes him so god damn hilarious, it's because he wants to be a good person - Or at least viewed as one. Often at times being no stranger to milking his pride and small accomplishments to peers, and lying all too often about the extent of his "heroic" feats. Though there's a duality between him & characters such as Aqua who expose and poke fun at each other and who they really are, and as a result he often times abandons his pride to become something much worse - Often showcasing Kazuma's warped and perverted side, letting the cat out of the bag so to speak. Throughout his adventures we see how hilariously greedy and selfish he can be and how needy and pathetic characters like Aqua can be. Often times having to facilitate a balance between his party members lack of any logic and overspecialization in a particular skill or lack thereof, by learning more basic and core skills one would need to normally go about in combat. 
So what happens when you stick another person who's just as shameless and selfish? A lot!! Kazuma only takes Aqua with him out of spite in his humiliation from her provocations and the fact that she's a goddess, not initially realizing just how absent minded and useless she can be, which leads to Kazuma often trying to abandon Aqua, only not being able to due to her tenaciously needy and desperate nature. Aqua is puppy like, often being energetic and absentminded, while seeking attention and praise for who she is as a goddess and everything between. Though both Kazuma and Aqua are not exactly entirely shameless though, and that's what makes it funny, because Aqua and Kazuma do have a sense of pride, in fact they're both very conceited and in Kazuma's case disgustingly so - But in a good and funny way. Though Aqua is quick to abandon her sense of pride, often prostrating herself before Kazuma, begging and pleading whenever Kazuma threatens so much as abandoning her, leaving her to pay her own debts, as she's easily upset and unfocussed when it comes to the tasks at hand.
The thing that infuriates Kazuma is that she's actually a talented prodigy, though she's to much of an airhead to actually make use of any of her magical affinity, though on occasions she does have her moments as her specialty is dealing with the undead as she is a goddess of the after life.
Megumin on the other hand is a young adolescent girl just entering her teen years at the tender age of 13, being a mage of the Crimson Demons - Often characteristic of black hair, red eyes and a strong case of chünibyō. She's stubborn in her single love for explosion magic, only knowing a single explosion spell with a massive area of effect and destructive power. Too much of an advanced spell that she's incapacitated for the rest of the day and can't use any more magic till the next. Due to the impractical nature of her spell, and overspecialization in a not so convenient explosion spell, she's hard pressed to find other party members until she stumbles upon the lowest of common denominator in Kazuma and Aqua's party of rag tag adventures. Asides from her explosion magic fetish, she's actually one of the more normal and amicable characters within Konosuba and to my knowledge is the only one within the entirety of the series to have any semblance of a more complex relationship with another character, being Kazuma.
Though not really elaborated on, Kazuma and Megumin develop a relationship and love over explosion magic, as Megumin is often inconvenienced with having herself incapacitated when practicing explosion magic, she has Kazuma piggy back her home after her daily explosion practice. If you see the first OVA, you'll see her reflecting upon Kazuma's acceptance into his party as a more important and memorable event in her life. You'll have to purchase the Bluray copy and for the second OVA you'll have to purchase the 12th volume of the light novel to receive the OVA bundled with it.Darkness on the other hand was the most problematic character for me, I feel director Takaomi Kanasaki & Natsume Akatsuki took both innuendo and shamelessness to a whole new level, in fact much to far. What's Darkness like? Just a mindless masochistic sex object that's all - Her lady proportions are grossly exaggerated, her personality is just desperate and disgusting, adding very little to no entertainment value, and adds nothing redeemable to the show as far as I can tell. Here's the problem, you already have relatively simplistic characters such as Aqua and Kazuma who are both conceited and shameless in their own ways, when you take that a step further and add a nymphomaniac to the picture who's sole function is to add cheap fan service is when your taking it way too far. Combat wise, as you might already have guessed her sole function is as a damage sponge, thanks to her high defence and constitution, though despite having the muscle she doesn't have the accuracy to hit Anything - Like Anything at all. (Except explosive clones that is)
“If such free-willed and bothersome people existed in real life… I’d firstly be slapping some sense into them” - Natsume Akatsuki
Wiz is probably one of may favourite characters oddly, at least compared to Darkness that is. Though more of a supporting character I find she fits the her role just fine, I love the way she emotes and how she's always amicable and helpful. Though not really seen much outside of her Magic Shop, she's usually seen aiding Kazuma's party in the most important of moments, often being their confrontations with the Devil Kings Commanders. Despite actually being one of the Devil Kings commanders, she was only tasked with maintaing the barrier surrounding the Devil Kings castle, though she breaks this neutrality between them when innocent non combatants are targeted by one of the Devil Kings Commanders - And when she helps out, it turns out she's quite a powerful bad ass herself. Despite her limited use in the story, she's a welcome addition, and when she has her own highlight moments, the contrast between her often timid and shy personality, to when she gets serious is always a great to see. She often has a lot of trouble with Aqua, being that since she's a former Devil King Commander, she's also undead as well, despite looking perfectly human, & Aqua always has a bone to pick when it comes to those who are undead or related.
What makes Konosuba excel as an anime so much was how improvisational and organic the dialogue the voice actors made the comedic banter seem. To make up for some other deficiencies, I feel the spirit of fun and laughter incorporated into dubbing is what made Konosuba just so god damn fun. Through the vivid emoting through character animations, lovely sequenced OST, and awesomely lively voice acting cast with stars such as Sora Aniyama as the ever wacky Aqua, Fukushima Jun and Yui Horie famous for roles such as Hanakawa Tsubasa in the Monogatari series, now reprising her role as Wiz in Konosuba - Despite Konosuba being simplistic as a narrative whole, with very simplistic characters in addition to that, the way characters interact and speak with one another is an entirely different story, as Akatsuke's Natsume's characters are anything but normal. It's this ongoing kinetic and organic interaction between characters that makes Konosuba as a story seem alive.
“Yeah, None of them are very normal”- Natsume Akatsuki
Due to Natsume Akatsuki's more improvisational techniques in writing and his tendency to make every and any character into another one of his dumb and helpless characters, Konosuba has a hard time finding a protagonist serious enough, to be the progenitor of a more important and greater story, as he's more fond of prioritizing enjoyment over story structure, and letting characters clash and coexist organically. As result Konosuba is far more about dumb fun and eccentric dialogue, which makes Konosuba much more of a character driven sense of entertainment, rather than a traditional story with an equal librium of balanced elements and a logical sense of progression.
Natsume Akatsuke on writing characters -“Mitsurugi for example, was supposed to be more of a proper rival but then he… turned into another helpless and dumb character…"
