The security in Japan is pretty good. As for how much, even if you drop the wallet with money, it is good that it remains on the spot or it is delivered to the nearby police box with the contents inside.
However, there are some places where security is not good.
The author, who has lived in Japan for 30 years, will explain the security around Tokyo.
The following two places are not particularly good images. (It’s just an individual opinion)
Kabukicho (north side of Shinjuku)
Southern Kawasaki (around Haneda Airport)
Kamata (a station on the way from Haneda Airport to the city center) is also a little bad.
The southern part of Kawasaki has an image of many pickpockets. There is no murder.
At first glance, Kabukicho is an ordinary bar, but there are some that charge a high price when you enter.
In particular, stop following the guide standing outside.
That was the security around Tokyo. Security is basically good throughout Japan, so don’t worry, you don’t have to be too careful except in the areas mentioned above!