Crazy Crab

Korean kids love the word crazy. If I had a dollar for every time I'd heard, "Teacher, she's crazy girl [sic]," or something similar, I'd be a very rich man.
So when I was walking on Orchid Island in Taiwan last month and I saw this hermit crab in a little cave on the side of the road, crazy is the first word that came to mind.
The crab was medium-sized and had taken as its home this plastic cup that looked like a small oil filter for a car.
Below, you can see its buddy, who had a more traditional shell.