Made in Abyss: The Golden City of the Scorching Sun

Riko, now equipped with a White Whistle, heads into the Abyss's sixth layer, the Capital of the Unreturned, accompanied by Reg and Nanachi. They aim to explore the uncharted domain and locate the ruins of the promised Golden City. As they navigate the harsh environment, they encounter various dangers, including hazardous creatures and treacherous terrain, which they must adapt to in order to continue their expedition. Their journey leads them to a village inhabited by the enigmatic "hollows," prompting them to investigate the settlement and uncover its secrets.