Created to prepare for coming threats, he serves as the teacher for Class 3-B at Sumanai School, a school for peace where eight students are enrolled. He possesses enough strength to instantly defeat any enemy using a diamond sword. He sometimes kicks opponents larger than himself with a 'Sumanai Kick' or blows them away with a 'Sumanai Punch.' Due to his strength and naturally kind personality, he is adored by his students as a reliable teacher. His catchphrase is "Sumanai!" (Sorry!). When doing something with great momentum, he repeatedly shouts "Ah, sumanai sumanai sumanai!!" When apologizing normally, he speaks quickly and looks a bit apologetic, saying "...Sumanai." He is in charge of light blue. He does not use honorifics. First person: I (soft, polite). He refers to his students as Mr. [Name].

He looks like an ordinary baby wearing white diapers, but he's an amazing baby with the voice of a middle-aged man. While he can walk and talk normally, his knowledge and judgment are understandably inferior to other members, and his personality is simple and a bit clumsy. However, his special ability is the power to talk to animals, which has often saved the day. Since he is a baby, he loves milk. First person: I (casual). Second person: you all (blunt). He calls members other than Sumanai-sensei with 'Mr.' In charge of green.

The brains of Sumanai School. A super genius with an IQ of 200, he looks just like his icon. Basically, special items are often established as things he created. He carries a laptop in one hand and hides his true face behind a black and white mask where only his eyes are visible. He gathers various data instantly with blindingly fast one-handed typing. Always calm, collected, and a serious stickler for rules, he also strongly recognizes the importance of his comrades and is the most reliable in a pinch. He isn't particularly good at combat, but his skill with firearms is second only to Banana, showing off his gunslinger skills by gracefully handling dual pistols. At Sumanai School, he shows off his genius by solving math tests that are on a completely different level from the others in seconds and conducting various experiments, but he also has a gap: he's a closeted sweet tooth and a fan of American comic book heroes (especially Batman). His private base is a highly high-tech room. Incidentally, currently only Banana knows that he likes American comic heroes. First person: I (formal). Uses polite speech. He calls members other than Sumanai-sensei with 'Mr.' In charge of black.

Wealthy and a bit self-centered. He looks just like his icon. He often butts in only to be the butt of the joke or silenced by Banana (with a rocket launcher or bazooka). At the very least, he is not a bad person. He often says "Haaaah!" before speaking. His special ability, fitting for a rich man, is the power to immediately discover rare minerals like diamonds and gold. This ability hasn't been very useful and is often turned against him, leading him to fall for pranks. Actually, when he takes off his glasses, his demeanor completely changes, and he exhibits tremendous strength for just 3 minutes. First person: I (casual). He calls members other than Sumanai-sensei with 'Mr.' In charge of gold.

A man of few words who looks like a banana wearing sunglasses. His voice is the deepest among the members. Due to his personality, he stands out a bit among his classmates. He always carries various guns and heavy weaponry, being active in many ways such as silencing Money or defeating villains and troublesome monsters. Also, when exterminating monsters, he is at a professional level in combat—creating simple traps to attack safely and basically retreating to regroup if he senses a disadvantage—making him a powerhouse in class alongside Sumanai-sensei. However, he also understands the importance of his comrades, protecting his classmates (even if Money is a bit much) and leading the charge ahead of others. He hates apples. First person: I (soft, polite). He calls members other than Sumanai-sensei with 'Mr.' In charge of yellow.

Mr. Blue's twin older brother. He is skilled at stealing things and possesses the special ability to shapeshift. He uses this to deceive others' eyes. Occasionally he gets caught, but he is cunning enough to destroy evidence skillfully. While he has talent in crafting, combat, and exploration, he is a self-admitted lazy person who often pushes tasks onto his younger brother by claiming a stomachache (which is, of course, faked); he is a so-called tsundere. He has an extraordinary love for spicy food and has a bad habit of dumping mustard or chili pepper on everything he cooks. On the other hand, he has a somewhat realistic side and doesn't really believe in fantasy things. First person: I (casual). He calls Blue his younger brother. He calls members other than Sumanai-sensei with 'Mr.' His weapons are daggers and bows. He can perform combo moves with Blue. In charge of red.

The blue twin younger brother who is pushed around by his rather troublesome older brother. He is skilled at creating secret bases and hidden rooms, as well as detecting hidden passages. In fact, Red and Blue's private room at Sumanai School is hidden inside a drained pool. He is a hard worker who gets various troubles pushed onto him by Red, but he fights back each time by blowing him away with punches, showing that he is also strong. Among his classmates, he is a voice of reason alongside Gin-san, and he is bad with ghosts. First person: I (casual). He calls Red his big brother. He calls members other than Sumanai-sensei with 'Mr.' His weapons are daggers and bows. He can perform combo moves with Red. His favorite food is ice cream. In charge of blue.

He looks just like his icon. A silver-colored Sumanai School student, as his name suggests, with the strength of being good at building. He is often called Gin-san. Using his naturally high building and crafting abilities, he will make anything for you as long as he has the materials. Sometimes when faced with unexpected events, he has a unique way of being surprised, saying "Oi-!?" Also, as the class's biggest voice of reason with a cautious and kind personality and high crafting skills, he is often assigned a support role. First person: I (casual). He calls members other than Sumanai-sensei with 'Mr.' His weapon is a hammer larger than his own body. In charge of silver or gray.