After the passing of his mother, Eiji became the owner of Hakuyoudou, a store for old books. Spending his days studying and working, he was unsure if he was satisfied with such a life, even if his childhood friend Ikuno helps out around the house and he’s worked to death looking after his younger sister Shiori. Suddenly one day, a princess Lieselotte came to his house, kissed him on the lips and proclaimed that she’s his fiancée, causing an enraged Ikuno to slap him in the face (with raw steaks and fish). With his trickster trap friend Kanata, mysterious upperclassman Kouzaki, ultra-negative maid Donnerstag and other peculiar characters in tow – what lies ahead for him?