The End of the World Begins with Captivity

The end of the world is coming and I am imprisoned by my top student at the same table? It's a pity that I have the ability to retrace my death. Look how I can go back in time and imprison my classmate! No, no, don't misunderstand me. I just want to survive the end of the world with him. So even if you imprison your deskmate, it's okay as long as it's to keep him alive, right? This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.