What is that thing he's in? It looks like some sort of crazy tupperware...
That's Durabilt modular storage bin; comes with its own lid and already has the right sized opening and a lip to hold in the shavings. Since it's plastic it's also easy to clean.
That, and sometimes roosters will try to find the best places for his girls to lay eggs. Roosters may not do much, but when it comes to their hens, they'll most likely do what they can to 'commit'.