Ravenous Mother - Two Gatherers by J. R. Kendiro

The Mother. A titanic organism, humanity's home and ravenous god. Housing sprouts like fungus from flesh, wrapped in membranes, supported by cartilage. No stone. No metal.

At the Last Fort, Bulelani is no ordinary crew leader. He can read, he knows how to move, he's respected. And he has a debt to collect – in blood.
Qaqamba is a fool. He talks too much, he's clumsy, he doesn't understand what's happening around him. But he'd do anything to avoid work. Even help a man get his revenge.

Five days, Two gatherers with nothing to lose. A perfect plan that won't stop falling apart.

"The Mother feeds the child. The child feeds the Mother."

Dark fantasy fans of Abercrombie, Lawrence, Brown, and Jemisin, take note!