Well we're going to need to know your main keywords before we can give you your LTKs... What is your niche/site based on?..
Apart from your site being based on naruto (or page) what does it provide? blog posts or wallpapers or episode links? or something else.
I suggest you register for Google's Webmaster tools, and then check out the statistics for what search terms are showing your page as a result. That should give you a lot of long tail keywords to target.
the best way to find longtail keywords is to check your own server stats, see some long phrases that were used in searches to find your site, then see where you rank on google for those pages and optimize your pages accordingly
I just wrote a post on that at Digital Products Review. Not sure if I am allowed to hawk my site like that or not. The link to the blog is in my signature. The post shows you how to come up with long tail keywords that you may not even get from keyword tools. I have used the method with proven success.
I use seobook.com free keyword research tool, I put in a short KW like "computers" and I get back every phrase that is searched with that kw in it from Yahoo, MSN and Google with a daily total of searches. That is how I find long tails. For example for computer I get the long tail: "buy gateway computer cheap" and hundreds more.
There are a few tools that can be used specifically to find long tail keywords: HitTail, Long Tail AdWords and Google AdWords Keywords Tool.