After eating the Fruit of Evolution, the donkey Lulune evolves into a beautiful woman! Seiichi’s harem just keeps growing… but shortly after a brigade of female knights, the Valkyries, takes Seiichi into the royal castle. What awaits him there is the beautiful brigade captain, Louise. She suddenly challenges Seiichi to a duel, but how does he fare...?! And what is the sad past that Louise hides?