The hardest thing to say about cyber punk is it's definition. To sum up what cyber punk means in reality - it generally covers the computing underworld of hackers, as well as various underground technology such as amateur military technology.
In fiction, cyber punk is considered a sub-genre of sci-fi, especially popular in Japanese animation (anime), although also seen in films such as Blade Runner and The Matrix. Generally, this type of fiction covers the subjects of computing, hacking and general mechanical technology.
It should be noted that cyber punk is not an officially accepted term in computer science, although it has been widely accepted as a laymans term in fiction.
That anime has mecha fights, computers that can access everyones brain, its a cyber punk anime.
An anime fan or fan of sci-fi in general who has an obsession with mecha - generally, anything mechanical. Mecha most commonly refers to giant humanoid robots, but can also refer to body-encasing armor and the like.