Voiced by: Yuusuke Kobayashi (Japanese), Daman Mills (English)
The main protagonist of the series. Initially your average Japanese salary man, he died in a traffic accident and was reincarnated in another world... where his new parents were killed by a demonoid while riding in a chariot. The then-toddler Shin was found by Merlin Wolford who raised him as his own grandson with the help of his ex-wife Melinda, growing up to become an astonishingly versatile mage. Too bad Merlin kinda forgot to teach Shin certain social and worldly skills...
- Adorkable: Thank to his lackluster social skills he is nigh-incapable of normal social interactions, resulting in many endearing moments. Then there is this gem. An adorable dork indeed.
- Affectionate Parody: Of the Stock Light-Novel Hero. He is incredibly strong, good-looking, etc. Yet in spite of all that, he is ultimately a Ditzy Genius with little to no social skills to speak of, resulting in many characters getting understandably flabbergasted by the juxtaposition.
- Apologetic Attacker: Apologizes to a demonized Kurt right before killing him.
- Badass Adorable: Was this ever since his early childhood and continuous to be one as a teenager.
- Bare Your Midriff: The cover of the Volume 7 of the Light Novel series is a textbook example. Male (Isekai) protagonists are otherwise relatively rarely seen less-than-fully-clothed on Light Volume covers.
- Berserk Button:
- He greatly dislikes his shoulder getting patted by someone else. It's mostly Played for Laughs.
- On the other hand, this is played seriously when Sicily is being threatened.
- Bishounen: He even goes as far as to describe himself "like a thin handsome fine youth, and could almost be mistaken as a face of a woman's."
- Boxing Lessons for Superman: Being trained by the greatest wizard, the best enchanter, and the finest swordsman, there was already enough to make Shin a top talent on his own. But what truly puts him over the top is the practical information he can gain from his Past-Life Memories. For example, to bolster fire magic, he can visualize the atomic components of the flame first, and then summon combustible gas to make it even more destructive.
- Cannot Spit It Out: At first, he and Sicily were way too shy around to each other to admit their feelings, but when their friends are talking about having kids in the future, she accidentally blurts out what she envisions for "our" (her and Shin's) kids. Shortly after this, Shin confesses his love to her and she reciprocates.
- Crazy Jealous Guy: Has a moment of this when he sees the Knight Academy cadets hitting on Sicily during a joint training exercise. He takes his anger out on an unlucky pack of demonised wolves though he goes overboard and destroys the landscape too.
- Ditzy Genius: Excels at magical abilities, but barely has any social skills.
- The Gift: Subverted. Everyone's initial reaction to Shin's incredible power and ability is to assume that he is just a natural prodigy at magic. However, it's stated several times that what Shin does can actually be done by anyone, once they know the trick to it. In reality, what makes Shin so gifted is the knowledge gained from his Past-Life Memories, such as knowing about the existence of atoms or how fire works, and applying that information to magic in order to bolster its effects.
- Healing Hands: He's actually quite good at healing magic thanks to the basic knowledge he gained in his previous life.
- Heterosexual Life-Partners: With August, as the first person to never take into account his status as a prince and just treat him as a normal person. As he says when they first meet, they are basically cousins due to how he sees August's father as an Honorary Uncle.
- Idiot Hair: Rather fitting for his personality.
- Just Think of the Potential: When Shin gets an idea for how to innovate new magical abilities, everyone around him starts to get worried, both because with his level of power his ideas can turn horrifically destructive and because it gets harder and harder to prevent outside parties from discovering them.
- Love Confession: After a brief period of awkwardness between himself and Sicily, he manages to confess his feelings and she in turn confesses hers.
- Luke, I Am Your Father: Is actually the son of Oliveira von Schtradius, aka Oliver Schtrom. He and Sicily later adopt Oliver and Miria's child Silver.
- Kung-Fu Wizard: Good enough in close combat to take down three fully grown men without magic, demonstrating his skill at hand-to-hand combat.
- Magic Knight: Aside from his magic training, he is also pretty good at swordsmanship.
- Meta Guy: Occasionally lampshades cliche situations and Stock Phrases.
- Mistaken for Gay: To his horror, his Heterosexual Life-Partner August and him get this from August's own fiancee. Luckily they are able to quickly clear up the misunderstanding though not without much embarrassment over the confusion.
- Mr. Fanservice: Noted to be quite good-looking. Granted, almost all Isekai protagonists tend to be conventionally attractive.
- No Social Skills
- Oblivious to Love: He and Sicily have blatantly obvious feelings for each other, but both of them are too shy to assume that their feelings are reciprocated. It's ultimately subverted when Sicily accidentally blurts out that she intends to have kids with him in the future. August points out what she said to Shin, who admits that he's not so dense not to understand what that means, to which August retorts that Shin was still dense enough to require such indisputable evidence.
- Past-Life Memories: His memories of his previous life are what really makes Shin the prodigy that he is.
- Person of Mass Destruction: Became this by the age of fifteen.
- Purple Is Powerful: His hair is purple and he is among the strongest characters in the cast.
- Raised by Grandparents: With the caveat that he was raised by an adoptive grandparent.
- Sacrificed Basic Skill for Awesome Training: The whole premise of the series is Shin learning to cast incredibly powerful magic at an early age, yet completely flunking at the most basic social skills thanks to Merlin forgetting to teach them to him.
- Shirtless Scene: The very first shot of the opening theme.
- Stock Light-Novel Hero: A former Japanese Salaryman who died gets to Reincarnate in Another World as an absurdly gifted youth with innate magical talent, combat prowess and an incredible moral fiber. He also enters a Magical Academy where his talents can be recognized. The only thing he doesn't have is a harem, instead getting a single Love Interest early on and just as early on making it official.
- Sufficiently Analyzed Magic: The key to his talents. Due to his knowledge of science from his past life, Shin is able to analyze and comprehend how magic actually functions and apply it in new, more effective ways that nobody ever thought of before. Technically anybody can do what he does, he's just the first person to figure out how.
- Vitriolic Best Buds: With August, who loves to make fun of his non-social skills every chance he takes.
Voiced by: Yusaku Yara (Japanese), R. Bruce Elliott (English, old), Austin Tindle (English, young)
Shin's adoptive grandfather. In the past he became renowned for stopping the first demonoid together with Melinda.
- Amicable Exes: In spite of their divorce, he and Melinda are in good terms. Melinda also comes him to visit every now and then, effectively becoming something of a grandmother figure to Shin.
- Cool Old Guy: Despite of all his accomplishments that made him a living legend, he is still a surprisingly humble individual and has an overall pleasant demeanor. After the carriage Shin's biological family was traveling in was attacked by a demonoid, Merlin also took it up to himself to grant Shin's deceased parents a proper burial, despite never (successfully) discovering who they were. There he found Shin who miraculously survived (possibly thanks to the rain). Needless to say, Merlin adopted, (clumsily) raised, and loved Shin like he was Merlin's own biological grandchild. Also, even though he aged, he is still an expert mage.
- Epic Fail: Forgetting to teach Shin the most basic social skills.
- I Was Quite the Looker: In his younger days he was quite the Pretty Boy.
- Red Baron: "Crimson Devil King", "God of Destruction", "Hero".
- So Proud of You: He is incredibly proud of his adoptive grandson, to the point of turning beet red or even crying when someone praises him for doing such a good job raising the boy.
- Tears of Joy: He is prone to bawling Ocular Gushers whenever he expresses pride for his adopted grandson.
- Took a Level in Kindness: In his youth, Merlin used to be rather violent and didn't care to solve things peacefully. Decades later, his present self is pretty much a Cool Old Guy.
- Wizard Beard: Shorter than most examples.
- Wizard Classic: Only lacks a hat.
Voiced by: Gara Takashima (Japanese), Cynthia Cranz (English)
Merlin's ex-wife who acts as something of a grandmother figure to Shin. In her youth she was renowned as The Guru, as she fought against a demoniod in the past alongside Merlin. Aside from that event, Melinda is also responsible for inventing a lot of tools which made people's lives easier.
- Amicable Exes: To the point that she often visited and helped raise Shin alongside Merlin.
- Cool Old Lady: She is one of the best magical tool inventors, and she's still well-versed in enchantment magic.
- Gadgeteer Genius: She specializes in enchantment magic, as well as developing practical, everyday uses for magic outside of the battlefield. It's because of these innovations that she's called The Guru.
- Hair-Trigger Temper: She always yells at Shin or Merlin whenever they act carelessly.
- I Was Quite the Looker: Like her ex-husband, she was quite good-looking in her prime.
- Magic Staff: Her weapon in the past.
- Red Baron: "The Guru", "The Witch".
- Silver Vixen: Despite being a woman well past her middle age, she has a flawless body and looks absolutely dynamite in a bikini—something that her younger proteges notice with great envy. She credits this to Shin's health and exercise recommendations, such as creating a device with a belt she can run in place on (a treadmill).
Voiced by: Shohei Komatsu (Japanese), Brandon McInnis (English)
The prince of the Earlsheid Kingdom and one of Shin's classmates. Despite of his status, he is easily one of the kinder characters in the series. Not that it stops him from teasing Shin every now and then.
- Beware of the Nice Ones: In spite of being a pretty fair guy overall, he still has his moments of manipulativeness.
- Bishounen: Has pretty looks befitting his role as The Good Prince.
- The Gadfly: Is unlikely to waste an opportunity to tease Shin's less-then-sufficient social skills.
- Generation Xerox: Just like how his father Diseum is a long time friend of Shin' adoptive grandfather Merlin, August is Shin's closest friend.
- Genre Savvy: He notices that Shin and Sicily are firmly entrenched into the Cannot Spit It Out stage and eventually speaks up and tells Shin to tell her where he stands. When the two of them hear Sicily accidentally refer to possible children as "ours" (hers and Shin's), August gives Shin another nudge. When Shin later complains about August being too nosy, August tells him that he was trying to prevent Shin from saying he'd "confess his love once the war was over", which in stories would guarantee Shin's death. A shocked Shin realizes that August was trying to defuse a death flag.
- Hair of Gold, Heart of Gold: Has blonde hair and is solidly benevolent.
- Heterosexual Life-Partners: With Shin, in no small part thanks to August being among the only few people who do not smother Shin with special treatment.
- I Love You Because I Can't Control You: He fell in love with his fiancee, Elizabeth, because she was the only person at his debutante party not to give him the time of day just because he was the prince.
- Mistaken for Gay: By his own fiancee no less! Due to his Heterosexual Life-Partners relationship with Shin and how he talked so much about him, Elizabeth got very concerned about their relationship. He started pushing Sicily and Shin together even harder in response to that.
- Royals Who Actually Do Something: He is of noble heritage and competent enough to be 2nd best student in class S, second only to Shin.
- Shipper on Deck: It's thanks to him that Shin and Sicily finally escape the Cannot Spit It Out stage and confess their love to each other.
- The Wise Prince: Well-versed in politics, a good person, and a skilled fighter that gets even more skilled under Shin's tutelage.
Voiced by: Rina Honnizumi (Japanese), Lindsay Seidel (English)
The third daughter and overall fourth child of the House of Claude.
- Barrier Warrior: She is slightly better at creating magical barriers than most of her classmates.
- Cannot Spit It Out: She and Shin were both mutually shy toward each other, despite their feelings. However, after Shin finally makes a Love Confession, she happily reciprocates and the two become an Official Couple.
- Clingy Jealous Girl: If Shin so much as looks at another girl, the temperature around Sicily drops to that of a freezer.
- Crush Blush: She is almost always sporting a very bright blush whenever she has to interact with Shin.
- The Cutie: She is one of the most meek and feminine characters on the show, and also considered one of the most attractive.
- Dude Magnet: Sicily often gets a lot of guys admiring her. They are then crushed upon realizing she's with Shin.
- Healing Hands: She's second only to Shin in this regard and gains the title of "Saint" because of this and her demeanor.
- Love at First Sight: By their own admission, she and Shin fell in love with each other the moment they met.
- Nice Hat: Wears a beret-like hat.
- Red Oni, Blue Oni: She is the blue Oni to Maria's red, being the more meek and reserved of the two.
- Rescue Romance: After Shin saves her and Maria from a group of harassers, Sicily was head-over-heels for him from that moment on.
- Shy Blue-Haired Girl: She's very shy and reserved and has bright blue hair.
- Single Woman Seeks Good Man: Falls for Shin after he saves her and Maria from some thuggish demon-hunters, more so after he later defends her from Kurt.
- Thanks for the Mammary: After they've become an Official Couple, she sometimes end up in compromising positions like this with Shin.
- In an omake, Melida teaches her to invoke this to seduce Shin, so she may have done it on purpose.
- White Mage: She specializes in support and defense magic, rather than the more offensive types.
- You Gotta Have Blue Hair: Her hair is literally blue. Shin even buys her a ring with a blue stone to match her hair.
Voiced by: Yuki Wakai (Japanese), Katelyn Barr (English)
Sicily's closest friend.
- Cute Little Fangs: She is drawn with these.
- Fangirl: Like most people in the kingdom, she is a humongous fan of Merlin and Melida.
- Fiery Redhead: Can be assertive and has red hair.
- Only Has Same-Sex Admirers: In an omake, she receives a bunch of presents and love letters. To her dismay, they're all from girls.
- Red Baron: Valkyrie
- Redheaded Hero: Fitting her dynamic with Sicily.
- Red Oni, Blue Oni: The red oni to Sicily's blue, being far more outspoken and brash.
- Running Gag: In the anime, she is frequently comically annoyed by the fact that she is the only one in her group who isn't in a relationship yet.
- Shipper on Deck: From the moment Shin and Sicily met, Maria tried to push the two of them together.
- Tastes Like Diabetes: Her reaction to some of the moments between Shin/Sicily.Maria: "Ugh... it's too early in the morning for my stomach to turn."
- Took a Level in Badass: Highlighted when she effortlessly beats down the same creeps that sexually harassed her and Sicily.
Voiced by: Yoshihisa Kawahara (Japanese), Christopher Sabat (English)
The father figure to Shin and the former Commander of the Knight Order of the Earlsheid Kingdom.
- Adaptation Dye-Job: In the manga and the anime, he has dark hair and eyes instead of the blonde hair and green eyes like in the light novel.
- Hunk: Fitting for a former military figure.
- Retired Badass: No longer a commander, yet still one of the best conventional fighters in the setting.
- Training from Hell: Implied he put Shin through this, as Shin looked scared every time he kept increasing their level of training. It paid off, as Shin is a top-notch close-quarters combatant on top of being a magical prodigy.
Voiced by: Keisuke Koumoto (Japanese), Jarrod Greene (English)
The eldest son of Duke Littenheim and one of the loyal escorts of August, alongside Thor.
- Childhood Friends: With August and Thor.
- Hunk: Younger than most examples in the series, being considerably more muscular than his classmates.
- Keigo: Speaks in a very samurai-like fashion.
- Mr. Fanservice: Usually Played for Laughs.
- Not So Above It All: He comes of as stern and morose most of the time, he is shown to be quite garish when it comes to muscles.
- Otaku: His interest for physical enhancement magic suggests that he is a muscle otaku.
- Sensitive Guy and Manly Man: The Manly Man to Thor's Sensitive Guy.
- Undying Loyalty: Towards August, to the extent that he was willing to decline an opportunity to study a type of magic he was highly interested in if it meant he couldn't keep on guarding August.
- Verbal Tic: Ends his sentences with saying "~degozaru".
Voiced by: Arisa Shida (Japanese), Morgan Berry (English)
The partner of Julius. The eldest son of Baron Flegel.
- Character Development: He initially hesitated to talk to August as an equal, but after meeting Shin he reached a point where he can't help but voice out his complaints and advice without hesitation.
- Childhood Friends: With Julius and August.
- Mangst: To an extent. Thor longs to become a knight, yet has insecurities about his appearance. Given that he grew up with Julius, it is pretty obvious where these insecurities come from.
- Megane: Pretty and bespectacled.
- Sensitive Guy and Manly Man: The Sensitive Guy to Julius' Manly Man.
Voiced by: Miyu Kubota (Japanese), Kristin Sutton (English)
The class mood maker of sorts. Her father works as an accountant.
- A-Cup Angst: She has issues about her size.
- Berserk Button: Don't mistake her for a child.
- Forgetful Jones: Frequently forgets things.
Voiced by: Toshiyuki Morikawa (Japanese), J. Michael Tatum (English)
A teacher at the Wizarding School who offers to "help" his student Kurt. In reality, Oliver is a demonoid who managed to maintain his intellect.
- And Then What?: He is implied to have an existential crisis, having no other goals in his life after completing his revenge.
- Benevolent Boss: He treated the commoners under him so well that others from other territories moved to his. Which angered the much less benevolent lords of the empire, who feared if he was made Emperor that he would make laws that... would help commoners rather than exclusively the nobles.
- Big Bad: The overall biggest threat in the setting.
- Blind Seer: Subverted. He pretended to be blind and wore dark shades to hide his demon eyes.
- The Corrupter: Under his influence, Kurt became far more selfish and egotistical.
- Freudian Excuse: He was betrayed, framed for a crime he didn't commit by nobility envious of his good reputation among the people, and his beloved wife who was pregnant was burnt alive.
- Fallen Hero: Went from being a textbook example of a Reasonable Authority Figure to becoming the main antagonist of the story.
- Happily Married: He and his wife Aria had a stable marriage and he was deeply devoted to her, without any concubines.
- I Never Said It Was Poison: Falls prey to this when he name-drops Kurt as the demonoid during an interrogation, when the King had specifically placed a gag-order on his identity.
- Man Behind the Man: The culprit behind Kurt turning into a demonoid.
- No Good Deed Goes Unpunished: He was a good nobleman, perhaps even the only one in an empire ruled by Evil Aristocrats, who sincerely cared about the welfare of the common people, and when he was falsely accused of a crime he did not commit, his own people betrayed him.
- Red Eyes, Take Warning: A sign of his nature as a demonoid, his sclera are bright red.
- Revenge Before Reason: Deconstructed Trope. He is so bent on avenging his beloved wife's death that he's reached a point where he has no idea what to do afterwards.
- Tragic Villain: A loving family man and benevolent noble who ended up as a villain after experiencing a horrible tragedy.
- Walking Spoiler: Being the Big Bad, he is the cause or is heavily involved in some of the most significant events in the story.
Voiced by: Daisuke Matsuoka (Japanese), Dallas Reid (English)
A highly snobbish student who ends up getting turned into a demonoid.
- Asshole Victim: Kurt ends up getting killed by Shin after turning into a demonoid. Slightly unusual for this trope, Shin is visibly disturbed that he ended up needing to kill a classmate, even if it was someone as rotten and arrogant as Kurt.
- Alas, Poor Villain: Despite the above, when they find out how Kurt was used by Schtrom, they are very upset, particularly how he used to be a decent person before Schtrom got his hands on him.
- Brainwashed and Crazy: Kurt used to be more reasonable in middle school before Schtrom got to work on him. Either through magic, mental manipulation, or both, he turned Kurt into the Hate Sink he is in the present.
- Green-Eyed Monster: Is extremely jealous of Shin for being in Class S while he only ended up in Class A, to the point of accusing him of cheating somehow.
- Hate Sink: Aside from being used as little more than a lab rat by Professor Schtrom (which was made possible in the first place by Kurt's own negative emotions), Kurt was written with no pitiful or redeeming traits.
- Never My Fault: Blames all his failures on everyone else, especially Shin.
- Off with His Head!: How Shin kills him.
- Politically Incorrect Villain: His views on women are... anything but forward-looking. When Sicily rejects his engagement proposal, Kurt ends up snapping and calling her a whore while saying that a women's only job is to obey and please their men. In the anime, however, this is Adapted Out.
- Red Eyes, Take Warning: The sclera of his eyes turn red when he demonizes. Combines with Glowing Eyes of Doom once he goes completely off the deep end.
- Screw the Rules, I Have Connections!: He does not seem to understand that this line of thinking doesn't work at the academy, as everyone including the crown prince are meant to be treated as equals. In fact, he only gets angrier when told as such.
- Stalker with a Crush: Towards Sicily; he hoped that she would become engaged to him.
- Starter Villain: Unwittingly ended up being the first direct antagonistic force Shin faces in the story.
- Tantrum Throwing: His room is a mess after he finds out Shin scored higher than him.
- Unwitting Pawn: To Schtrom, who turns him into a demonoid.
- Used to Be a Sweet Kid: Up until he joined Schtrom's study group. Before that, he was still cocky but he never abused his status or looked down on others.
- The Von Trope Family: A darker example. He is very elitist and operates with extreme classism, looking down on anyone who isn't a noble.