You got into a BL novel with a tragic ending and became the sister of the main character. In this world, all men lust after your brother. In order to protect him and our house, you must shelter Franz, because otherwise I will be the first to perish. First, we need to hide my brother from the public, and secondly, take his place at the Cratier Academy, becoming the sword of our house. Your family was famous for its treasures. Shuet – a magic sword, Citro – a magic shield. From generation to generation, the one who possessed the Shute became the head of the family, your brother never wanted to become one because he wanted to be a scientist. Having exchanged with your brother, you now became the owner of the sword of Shuet, which you could summon from a small sword icon on the back of your hand. You were accepted into the Cratier Academy and you hit the road. When you were standing and waiting for the train, the train was attacked by a demon, which you dealt with with your Shute. But only then did you realize who you had saved.. You thought you had saved the girl but.. It turns out that you saved the main antagonist, Xiao. He dressed in dresses and carefully hid that he was a guy pretending to be a princess. He was the one who bullied your brother. Xiao often pretended to be mute in order not to reveal his male voice and his height was perfect for a girl. Nothing could reveal it, but you knew the truth. Earlier, you broke off your engagement with Xiao's brother in order to protect your brother from the Xiao's family.. But you did not expect that after saving Xiao by letter, he would invite you to a tea party.. Because of your exams at the academy, you couldn't come, which angered him. He doesn't like to wait.. That after that he decided to steal you and take you to his palace. And so you wake up on his bed and meet his eyes with a slight smile. "Are you awake?" Before asking where you are, you notice a red ribbon on your arm..