Megumin is a young girl with shoulder-length dark brown hair (smooth black in light novel) and crimson-colored eyes. She wears a classical witch attire such as a black cloak with gold border, choker, wizard's hat, fingerless gloves, and carries a black staff. Though she jokingly claims that her eyepatch seals her immense power, she actually sees it as a stylish sense of fashion due to her chuunibyou tendencies. Megumin's right leg is wrapped in white bandages, although she has shown to be able to remove the bandages and she has no visible signs of injuries on that leg.
She has fair skin and a light complexion. Unlike her rival Yunyun, who has a more developed body, Megumin seems to have a delicate under-developed figure, as Kazuma describes her figure as a "porcelain doll." Yuiyui also stated that all of their family members have thin bodies, but Megumin thinks that it's just because they lack nutrients because they hardly eat solid food.
Megumin is a loud, boisterous, and eccentric girl with a flair for theatrics. Being a member of the Crimson Demons, she shares many of her people’s characteristics, such as displaying chuunibyou tendencies and having a fondness for strange names. Megumin often comes off as cocky and arrogant, constantly boasting about her destructive powers, but is quick to drop her act when put in a desperate situation, such as when Kazuma threatened to slap her with her eyepatch.
Though she plays the part of the supremely powerful wizard, Megumin is actually quite childish and immature. She is sensitive about her age and underdeveloped body, becoming either despondent or aggressive when treated like a little girl. She maintains a somewhat petty rivalry with her old classmate Yunyun, and never misses an opportunity to bully and harass her, despite secretly seeing her as a friend.
Megumin is utterly obsessed with explosion magic, investing all of her stat increases in her one explosion spell, despite the spell draining all her energy after one use and being generally impractical. She refuses to learn any other type of magic, routinely flying in the face of all logic to protect her explosion magic. Because of her obstinance, no other party will have her despite Crimson Demons being known for their powerful wizards, and Kazuma only accepted her after she blackmailed him. She demonstrates zero self-control when it comes to her explosions, and will often completely disregard any consequences as long as she can cast one explosion spell a day. The most egregious example of this is when she continued to blow up one of the Demon King’s General’s castles, even after he came with his army and specifically threatened the entire village to stop.
Despite her short-comings, Megumin is acknowledged by Kazuma as having the most common sense of the group. She was the only one besides Kazuma who recognized the bizarre and cultish nature of Aqua’s religious followers. As a Crimson Demon, she is fairly intelligent and is legitimately adept at magic (though she limits herself to only one spell). Megumin also does show genuine love and loyalty to her friends, and will fiercely protect them if necessary.
While still attending school, Megumin would swindle food from Yunyun every day since her parents couldn't afford meals. Due to her exceptional academic performance, Megumin was able to graduate early. When she left to travel alone, Yunyun predicted she would be "at a loss due to a lack in the means of survival, begging a useless guy for a meal."
After traveling to Axel Town, she quickly gained a reputation as a crazy Explosion fanatic, thus parties refused to accept her before she met Kazuma and Aqua.
Explosion Magic: Megumin is absolutely obsessed with Explosion magic. She devotes all of her skill points into improving the power of her explosions, shortening her casting time, and being able to cast the spell without chanting out loud. The spell itself is shown to be incredibly devastating, often obliterating anything within its targeted range and even sending out powerful shock-waves that can be felt hundreds of yards away. However, the severe mana drain, combined with Megumin never using points to increase her mana, results in her always collapsing after casting and becoming completely immobile. Also, her refusal to learn any other magic makes her entirely dependent on allies after casting. This is especially notable because there are other known Arch Wizards who can use Explosion magic, can remain standing after casting, know at least one other skill, and can fight alone if necessary.
Intelligence: Compared to the four members of her party, Megumin's stats are the highest in terms of intelligence and she is shown regularly to be clever when the situation demands it. However, said intellect is commonly hindered by her chuunibyou tendencies, best shown by her refusal to learn any spells outside of Explosion despite the obvious limitations that come with it.
High Magic Proficiency: As a member of the Crimson Demon Clan, Megumin is naturally gifted in terms of magical ability and has been stated to have high mana reserves as a result. Were it not for her desire to focus solely on Explosion magic it's very likely she'd be able to use a wide range of advanced spells like many of the members of the clan.
- "Megumin" is a Japanese nickname commonly given to girls named "Megumi," which means "blessing."
- Her name is presumably a pun on the KonoSuba title, as the "Shukufuku" translates to "Blessing," or "to bless."
- Her nickname "psycho girl" or "the psycho one" is a pun on "saikō" (最高, "the best"), the word she frequently says after releasing an explosion magic.
- Megumin sends a portion of her savings back to her family each month, but avoids sending too much or else her father would waste it on making useless magic potions. In total, her personal earnings for the entire year have been less than 10 million eris.
- Due to her tendency to steal the final blow, along with the spotlight, Megumin receives the bulk of the experience points earned by each of the party's conquests, leading to her being the highest level in the party at around the mid-40s.
- She has a barcode birthmark on her butt.
- Her purse is full of shopping points cards and coupons, even after becoming a multi-millionaire.
- Megumin's birthday is on December 4th
- “Wahahahahaha! My name is Megumin, the number one mage of Axel! Come, you shall all become my experience points today!"