Motley Milius is the son of Cain Milius, initially next in line to the throne before Declan deposed him, turning him into a spider-like mutant and casting him into the Final Disposal Site. Driven mad by the Fumes and the fear of losing any more than he already had, he transformed into a gigantic spider that endlessly hoarded garbage, known by the other Homunculi as the King of the Garbage Heap. When Tuned, he grants Lilac the ability to use his silk as a grappling hook to reach higher points and, when enhanced later, projects a webbed barrier that allows her to continuously dash underwater.