Dave:
(1) "Ken" can mean all sorts of things in Japanese, especially when it's part of a larger word...this is common, and why written Japanese is pictoral in nature, and spoken Japanese relies greatly on context.
I don't read "Raijin"--I'm already up to my ass in manga as it is--and without a picture of the kanji to go by the best I can do is this:
"Nanha" probably means "southern (nan) school/sect (ha)."
"Kokamon" is a variety of Japanese tree, and also the name of a shrine in Nikko.
In "Gokeiken," the "go-" is an honorific prefix. Some Japanese words take "O-" (like "Ocha," green tea), others thake "go-."
"Keiken" can mean either "experience," or "pious, devout, or reverent." Again, if I saw the written word, I'd know for certain.
(2) When you reply to trolls, you're feeding the Matrix.
(3) You're going to have better luck with this sort of thing at forums devoted to manga and/or anime.
This is a possibility, and typing "manga forum" into Google.com will provide plenty of other options.