Wall Sina, Goodbye: Part One

Wall Sina, Goodbye: Part One (Wall Sina, Goodbye (前編)) is the sixth OVA episode of the Attack on Titan anime. It was produced by Wit Studio and Production I.G and released along with a special edition of volume 24 of the manga. It will be followed by Wall Sina, Goodbye: Part Two in April 2018 and an OVA based on the Lost in the Cruel World story in August 2018.

The three episodes are anime adaptations of the spin-off manga Attack on Titan: Lost Girls, written and illustrated by Ryōsuke Fuji, and based in turn on the visual novels Wall Sina, Goodbye and Lost in the Cruel World, by Hiroshi Seko.