Well, there's not really a need as such, for explicit swear words. I know the childish ones, such as uncou, which is "poop". I also know bakayarou and yarou - they pretty much mean bastard. Temei can be used the same way. Aho means something similar everywhere baring Osaka, where it's actually a familiar term of address if you're calling someone a fool. kusou and chikushō is sh*t, but it's more used like we use "damn".
There are others, like sl*t ect, all the ones to do with sex, but I don't think I'd ever bother with them.
If I ever wanted to be insulting I would just drop all the polite tenses from the verbs, and change the "you" to either omae (which isn't so impoliete for guys, but it is if a girl uses it. Or I would use temei, which would be more impolite), and probably change all my verbs to the imperative form. And start sticking "me" everywhere, as it's a suffix which makes other words more contemptuous. Sort of like the opposite to tacking "O" onto words to make them more polite.
It's hard to explain it by comparing it to English, but you can be jaw droppingly rude to another person without actually saying a swear word. You can also be achingly polite in speach and be staying some not so nice things.
Personally, that's one of the things I find so fascinating about the language. If debio's around he probably knows some swear words that are worse.
to those in need.
You did it. you did it.
