My grandfather was an arachnologist (someone who studies spiders - kind of a niche field), so I grew up around a lot of spiders. Tarantulas are tame (I had one as a pet. His name was Chewie, after the Star Wars Chubaka); black widows, though small, you ignore at your peril. Now is spider season in Japan. My strong suggestion is to allow spiders free-reign, particularly the big guys. There are no dangerous spiders in Japan. Which do you prefer, spiders or cockroaches? - William