In martial arts, the goal is to control the opponent, but in Aikido, the ultimate goal and essence is not to fight. Ryuichi Hashimoto, who studied Aikido under the teaching of ``Aikido is Aikido,'' returns to Japan after completing his training in Sweden. Ryuichi ends up living at his teacher Kodaira's dojo, but the day after he returns to Japan, a dojo breaker appears at the dojo...!?

This is the story of the mysterious ninja "Hisho" who continues to protect Makoto in accordance with the will of her late mother, who was the nanny of the only daughter of an old family, the Kodo family.