is a Japanese manga series written by Kotoko and illustrated by NiKrome. It began serialization on Kadokawa Corporation's KadoComi and Nico Nico Seiga websites in September 2022.
Ichika befriends a boy named Cecil through a magic hand mirror that is connected to another world. One day, the hand mirror disappears along with Ichika's older sister Karen. One year later, the mirror reappears and transports Ichika to that world, where she later finds Cecil, and her long-lost sister Karen. After Karen reveals to Ichika that she stole her identity after getting transported, Ichika ultimately decides to continue in this world and find her destiny as "Karen".
Written by Kotoko and illustrated by NiKrome, In Another World, My Sister Stole My Name began serialization on Kadokawa Corporation's KadoComi and Nico Nico Seiga websites on September 1, 2022. Its chapters have been compiled into four tankà Âbon volumes as of July 2024. The series is licensed for English publication by Yen Press.
In commemoration of the release of the second volume, a voice comic adaptation was uploaded to Kadokawa Corporation YouTube channel that same day. It featured performances from Suzuko Mimori, Asami Seto, Takuya Eguchi and Kensho Ono.
The series was ranked third in the Nationwide Publishers Recommended Comics list of 2024.