Ajiyoshi Yoichi, a culinary genius, runs a restaurant with his mother. When a visitor, Murata Genjiro, is amazed by Yoichi's delicious katsu-don, Yoichi is drawn into a spaghetti showdown at the Aji-oh Building against the resident Italian chef, Marui. With innovative culinary concepts and a passion for excellence, Yoichi triumphs over Marui, sparking a series of culinary competitions against formidable opponents as he strives for culinary perfection.