The Twin Contract

## Setting: The Academy in Ruviel's Royal Capital The elite Academy in the royal capital of the Kingdom of Ruviel is the most prestigious institution for training mages. Most of the story takes place within its walls. - The entrance ceremony altar: Where new students stand and stake their names. It's also where you first faced countless stares under Sion's name. - The dormitory wing: Living quarters lined with marble staircases and gilded corner ornaments. Since you're face-to-face with your roommate Erin day and night, it's the hardest place to keep your secret. - The School of Magecraft: Theory and practice unfold in lecture halls glowing with magic circles. It's where Dean Ashby's gaze can reach you. - The library at night: A quiet stack room where lamplight lingers even after lights-out. It's where you end up following the traces of the knowledge Sion meant to learn.

## Characters and Factions The Academy ranks everyone by bloodline and mana. Sion, with the blood of the highest nobility and a genius talent, carried everyone's expectations. His apprentices and underclassmen followed him devotedly—and so, now that you've appeared with his exact face, they suspect you might be Sion, or might not. - Corvin Ashby: Dean of the School of Magecraft. He seems to know your secret, but why he hasn't exposed it is a mystery. He tests and observes you with courteous words. - Erin Hale: Your bright, easygoing roommate. She approaches you warmly but never lets go of her doubts, and she's trying to dig up your secret. - Sion Morgan: Your dead brother. He whispers beside you in the form of a soul, just as gentle as he always was with his younger sister. - Academy headquarters: It sent you an official summons, citing the records Sion left behind.

## Rules and Terms: Names, Mana, Stand-ins In this world, a name is existence itself. The name of a house's heir carries immense power and a fixed destiny. The name you use belongs to Sion, so you must shoulder its weight as well. - Stand-in: Taking Sion's place. It doesn't end with imitating his face—you have to live out his relationships, his studies, even the way he talks. - Exposure: If your identity comes out, it won't end with expulsion; it will lead to legal punishment. - The twin-soul case: A rare phenomenon that occurs when twins share the mana of a single soul and one of them is gone. Dean Ashby cited it from an ancient text. - Inherited mana: After Sion died, your once-ordinary mana grew rapidly stronger. Every time you use magic, you hear Sion's voice.

## Atmosphere and Tension On the surface, it's a glamorous, refined Academy filled with gilded ornaments and the glow of magic circles. Inside it, you wear a face identical to his, like a mirror, and keep a precarious performance going. People's gazes are polite but sharp, and the murmur of the lecture halls alternates with the silence of the library at night to build the tension. The more your power grows, the clearer Sion's presence becomes, and the fainter your own place. A moment will come when you can no longer be sure whether it's you or your brother speaking and moving. Whether freedom or an eternal shadow waits at the end of this contract, no one can yet say. That unease is the emotion running beneath the entire story.