6th Layer

The Capital of the Unreturned, referred to as "Shourou" Layer by Gaburoon and translating to "The Capital of the Unreturned" in the language of the former native tribe that Ganja had encountered, is the 6th layer of the Abyss.

It is the point of no return, since it is physically impossible to survive the ascent from here, at least in human form, hence the name. When a White Whistle Delver descends down to the 6th Layer, it is called "The Last Dive," as none of them ever see the surface again.

Description
In the Capital of the Unreturned, the ruins of a majestic city sleep undisturbed. A rumor in Orth exists about a Golden City sleeping at the bottom of the Abyss, which supposedly originated from this very city within the 6th Layer. The city itself is described as golden—however, the ruins are covered by a crystalline material. It is unclear whether the buildings were intentionally made out of this crystal or if they became fossilized over time. The ruins themselves spread out in every direction, and oftentimes buildings are diagonal, upside down, or sideways. Creatures of to  danger level become quite common, as are random, bright geo-thermal explosions that emit poisonous gas. Bird repellent used on the Mail Balloons does not work on the aviary species in the 6th Layer.

The Curse that manifests upon ascending within the 6th Layer subjects the victim to an inconceivable pain and leads them to mutate into a messy pile of meat. Humans sometimes survive the effects of the curse, but their intelligence and consciousness vanishes, and they devolve into a mindless pile of flesh with only basic instincts. Under certain circumstances humans may turn into Narehate with their mind intact. It is also possible for those affected by the curse to simply die, which, of all things considered, is perhaps the more merciful outcome.

It is here that The Village of Iruburu came into existence, with the Three Sages in charge of it.

Beyond the village extends more steep scenery with more ruins as well as occasional fields of Eternal Fortunes and the habitat of the Emperorshells, which exceeds the depth of 14,000 meters, accompanied by flaming iron rain.

Located in an isolated section approximately 300 meters before the beginning of the 7th Layer is an outpost used by Hail Hex, the Delver group lead by the White Whistle Delver Srajo, to operate in the 6th Layer.

A physical barrier known as "The Eye" exists at the threshold of the 6th and 7th Layers.

Species

 * Amaranthine-Deceptor
 * Emperorshell
 * Fuzosheppu
 * Hermit Rat
 * Irumyuui's children
 * Kamazuno
 * Mizoujack
 * Narehate
 * Pseudowater
 * Turbinid-Dragon
 * Unknown Creatures

Flora

 * Daji Cone
 * Eternal Fortunes
 * Kashita
 * Sainona

Individuals

 * Ajapoka
 * Belaf
 * Cravali
 * Enbelietz
 * Faputa
 * Frapam
 * Gaburoon
 * Gaume
 * Girl-type (Sightings)
 * Irumyuui
 * Juroimoh
 * Maaa
 * Majikaja
 * Menae and Sherumi
 * Mepopohon
 * Minor Characters
 * Mitty (Replica)
 * Moogie
 * Nishagora
 * Pakkoyan
 * Poriyon
 * Srajo
 * Shurekaka
 * Tepasté
 * Vueko
 * Wazukyan
 * Yataramaru

Artifacts

 * Cradle of Desire
 * Crumple Pot
 * Gentle Knock
 * Mermaid Burp
 * Rigid Washer

Points of Interest

 * Ido Front
 * Altar of the Absolute Boundary
 * Miniature Garden Of Dawn


 * The Village of Iruburu
 * Belaf's House
 * Doguupu
 * Iruburu's Market of Value
 * Mepopohon's Inn
 * Narehate Restaurant
 * Poriyon's Workshop


 * Camp 5 on the Furthest Edge of the Abyss


 * The Eye

Trivia

 * During their travel, Riko documented and named various landmark points the group encountered such as a Mizoujack nest, sun bubbles, two clocktowers, a cliff side she named "The Farthest Great Plains", a spot featuring a deceased Delver, and another cliff near the habitat of the Emperorshells which was named "The Cliff of Emperor Mitty".
 * Due to the 6th layer being cut off from the 5th layer and higher, it's said to contain nothing but creatures no one has reported before except the creatures documented in Lyza's notes.
 * It's said that the buildings in the 6th layer are all a mix from different eras.
 * 'Shourou' means bell tower.
 * Nether Glyphs written on the map of the Abyss shown in the first chapter of the manga read 'やらずあめのとし' meaning 'city of rain that starts to fall as though trying to prevent a guest from leaving.'