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 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 novel "Wall Sina, Goodbye", by Hiroshi Seko.