Ranma, whose hometown was once attacked by a "Fallen Angel," was saved from a desperate situation by a summoner girl and dreamed of becoming a summoner himself. "I'll do everything I can. To become a man worthy of her...!" In a world where the size of the summoning circle is considered everything, Ranma, who could only produce a summoning circle 3cm in diameter, was looked down upon by those around him, but he continued to train every day without rest to become a summoner. Just then, Ranma found a secret plan and succeeded in calling forth a summoned beast, and the Tag with that partner exhibited out-of-the-norm Synergy...!? Aiming for the strongest summoner with the smallest summoning circle, an ability Battle x royal road Fantasy begins!!