GrappleSeed

Turner and Issadora are two teens with big dreams, but the world they live in is literally turned on its head. The sky is down and the ground is up. Anything that falls into the sky is lost forever. Humanity has adapted to living in this world and are happy with what they got. But Turner and Issadora knows that there's much more out there than the city they live in... threats that will change everything and ruin what they hold dear. To stop this threat they have to go out in a world without a bottom. This is the impossible journey. Tagged as Nordic Manga by the publisher Official website.