Whether you are planning a manga-style game or just intend for the odd Japanese villain to turn up in a more standard comic-book based campaign, this work contains some intriguing and well-developed flavourful villains to keep your vigilantes on their toes.
Mechanically, they have been worked through thoroughly, and each is provided with a detailed background liberally sprinkled with ideas of what they might be up to and how they will interact with the characters. Illustrations are stylish and give a Japanese feel without being too jarringly different.
Many of the villains are presented in groups, or at least associations who may or may not be working together, but there are also several 'independent' villains who normally work on their own. The notes include sections of information likely only to be available to those with contacts within law enforcement as well as more public knowledge, the sort of thing that may even appear in the news and is certainly accessible to anyone who can be bothered to do some research.
If you accommodate the supernatural, there's a vampire and the odd devil mixed in: in a world with superpowers rampant it is quite within the bounds of possibility even if they have not featured in your campaign to date. Indeed, it could be quite amusing to bring, say, vampirism into your game by means of a Japanese visitor to the mean streets your vigilantes patrol, watch them wonder if it's the sort of vampirism they know from fiction or some Asia-specific import.
A nice selection - and there are some character-specific counters as well as generic 'agent' ones if you want to map out the inevitable brawls.