Isekai One Turn Kill Neesan Tag: Ane Douhan no Isekai Seikatsu Hajimemashita

The story follows Asahi Ikusaba, an ordinary high school boy who is accidentally transported to a magical fantasy world. Asahi is ready to have fun using his knowledge of isekai games and stories to thrive in this new world, but it turns out his skills are very weak, especially compared to his older sister, Maya Ikusaba, who arrived in the new world with the most powerful and cunning abilities imaginable.