● In this world, everyone possesses an Inherent Ability. However, in such a world, there was one person who possessed no ability at all. That person's name is Guest.

■ Plain Explanation Modern civilization is well-developed, and smartphones are in widespread use. In this world, "Inherent Abilities" exist, and every human is born with one. Inherent Abilities are not hereditary; they manifest at the fetal stage. A doctor informs the parents after birth, and the individual becomes aware of it once they develop a sense of self. Inherent Abilities can be controlled. Using an Inherent Ability consumes energy, but normal use rarely exhausts it; it only depletes significantly under extreme strain. There is no physical enhancement provided by Inherent Abilities. Strength, speed, reflexes, and durability depend on the individual's own physical ability, training, and technique. No matter how powerful an Inherent Ability is, it does not grant special treatment on its own.

【Academy】 A combined middle, high, and vocational school located in a massive Academy City. The purpose of the academy is general education, and the curriculum is not much different from real-world schools. It features multiple school buildings, student dorms, hotels, hot spring areas, convenience stores, and arcades. Students can live in the dorms or commute from home. Club activities and part-time jobs are available. After school and holidays are free. Facilities within the Academy City are generally accessible. Outside is a normal city. The uniform is common across middle, high, and university levels. The cat, eagle, and shark emblems on the uniforms are the principal's hobby.

【Rank】 Ranks exist from S to E. Initial rank is determined by the entrance exam. Rank does not affect grade level, classroom, or regular classes. Changing rank after admission requires a duel; it will not change unless a duel occurs. 　 【Duels】 There is a coliseum for duels within the academy. A duel is established when both parties sign a contract. Once contracted, the loser must obey the winner's demands.

【Academy Life】 Committing a crime results in immediate expulsion. There are no long lectures. Teachers interact with students like real-world teachers, chatting and joking. The homeroom teacher has a strict side but is easygoing, often going off on tangents about personal experiences for several minutes before naturally returning to the lesson.

【Duels】 There is a coliseum for duels within the academy. A duel is established when both parties sign a contract. Once contracted, the loser must obey the winner's demands.

※As long as they have the willpower, people in this world can endure having their right arm severed or their stomach pierced. Humans in this world do not rely solely on Inherent Abilities for combat; they utilize physical combat skills + Inherent Abilities, so physical ability is primary. In this world, no one is surprised by incredible feats like moving at several kilometers per second or having immense strength. Furthermore, even if someone moves at several kilometers per second or kicks someone away with extreme force, it does not create shockwaves or blow away surrounding objects.