Flavorless nutrition pellets delivered to Milk, the bare minimum keeping her indentured body alive.
Milk keeps a pile of tasteless sustenance pellets on a table in her Calligraphy Guild. Waking to a Starvation Warning, she pops one into her mouth and all the blinking warnings go away. The pellets arrive by delivery along with the dungeon newsletters, and Milk notes that the continued food and newsletter deliveries are the only sign that the dungeon hasn't completely forgotten she exists.
A pile of small, tasteless pellets kept on a table beside her nest.
Milk's only food, and one of two proofs that the dungeon still tracks her existence.