The Yearning Isle is a large island landmass surrounded by an ocean of water and ruled by Ledrosa, Archduchess of Lust. The largest of the current domains, the isle draws those souls filled with desires, lust, and gluttony and only allows those with enough cunning and strength to make it past all those who wander into this land. Being the creature she is, Ledrosa rewards those who succeed with all they desire.
At the center of the sea is the Yearning Isle which is occupied by Ledrosa. The "sea" is infested with monstrous and deadly creatures that attack anything that comes near them. The isle itself isn't better as the outskirts are littered with lost souls that had gone insane and other demonic entities.
Only when they finally reach the inner sanctum do they find what they truly desire, as Ledrosa takes pleasure in rewarding those who prove themselves worthy. For those seeking the pleasure of the flesh, Succubi wander the halls looking to reward wanderers and to corrupt their souls further.