My Special Ability is Growing Muscles

There are Humans. There are Elves. There are Dwarves. There are Orcs. And then there are Demons, and the Demon King.In a world where warriors wield elemental fury, assassins bend shadows, and mages rewrite the laws of reality with a thought one boy awakens the weakest and funniest ability of all.[Muscle Genesis] the power to grow and control muscle.The f*ck? No sword aura, no magic affinity, no flashy technique, just raw, brutal power.Born in the wild slums of Arcanum Nexus, orphaned, starving, and forgotten by the system, Kairo Vale has one goal: survive long enough to rise above it all.When his chance finally comes in the form of the prestigious Nexus Academy Entrance Tournament, the world expects him to fail, just another Unranked slum bastard with a useless ability.But the thing about muscles is that they grow.And so does his pain tolerance, and his strength, and his will to endure.Thrown into trials designed to break him, teamed with nobles who want him gone, and hunted by powers that fear what he might become, Kairo fights back the only way he knows how: one rep, one punch, one brutal threshold at a time.Because in this world, power is everything.And he's going to build his from the ground up.If they won't give him a place in their world, he'll carve one with his fists.