When a magic circle engulfs his classmate, Chisato, Kaito Arihara is whisked away to an unknown realm where he encounters Schiff, a shape-shifting cat monster. Discovering Kaito's unique mana, Schiff becomes his familiar. Surprisingly, Kaito's fighting prowess surpasses using his newfound companion. As he navigates this new world, seeking his place, Kaito faces the challenge of reuniting with Chisato, meeting a girl named Leafa, and uncovering the hidden demon king's machinations. Amidst the chaos, Kaito embarks on an unconventional journey in this comedic adventure of 'Hit-Tamer' in a fantastical realm.