Light-eater

The Light-eater is a creature featured in Made in Abyss: Binary Star Falling into Darkness.

Description
Light-eaters are birds that look beautiful when they spread their wings.

Despite how they look, they can barely fly.

Their legs are fused with their tail feathers, serving as a sort of wing, and they use their tails to stand.

They can't walk normally, but rather flap their wings to slide around and can aslo use them to hump short distances.