There is a peculiar space in Japanese houses called the "genkan." Although "genkan" sounds like a Japanese English abbreviation for Genghis Kahn, the genkan has little to do with conquering and more to do with barriers. The genkan is the welcome pit just inside the front door that serves as a gathering place for shoes, spiders and guests.
When you enter a Japanese house, you leave your shoes in the genkan and proceed into the rest of the house in slippers. Unless you live in an apartment. In this case, the genkan is probably so small, you can't even see the genkan floor for the heap of shoes. Upon entering, you trip over the heap, which conveniently launches you out of your shoes and into the apartment. Forget the slippers.
Spiders like the genkan. Since spiders have eight legs, it's not surprising that they're barefoot and fashion-starved. They enjoy living in the genkan, where they can try on all the different shoes. Most genkans have a resident spider.