The Worst Japanese Word You Can Say （くそったれ）

He Says:
kusottare　（くそったれ）=fucking shit,mother fucker
kusottare is my favorite one. It's very easy to say for me! The original meaning is a shitter in Japanese.
When we feel so angry, we say fucking shit or something. At the same time, Japanese say kusottare.
It's a little interesting both languages has shit in each word.
It'll be more japaneselike accent if you accent in "u" of kusottare!

She Says:
This is by far considered to be the "worst" word that there is in Japanese. It literally means "person who cannot stop the shit from running out of their ass". One wonders if you would use it for someone using diet products like Alli. But I digress...
This word actually has a special meaning for me. Before I met Him, I was living near Tokyo. I had a good friend who I'd known since high school. As we've mentioned before, Tokyo people tend to be a bit more polite and than others in Japan. So while I would always pressure my friend to teach me the dirty words, he never would. He didn't want me messing with "the beautiful language".
Anyway, one night I was out with my girlfriends and this dude picked me up. Well, actually, I suppose his friend picked me up for him. See, the guy didn't speak ANY English, but his friend did. So the guy would talk to his friend in Japanese and the friend would translate. I'm a sucker for any guy that calls me beautiful so...
I decided to go out with him a second time. This time the friend wasn't there, but I was feeling ready to try my Japanese. It completely sucked at the time, but I would always try to ganbatte (do my best). So we're hanging out, having a good time with another friend and his girlfriend (neither of whom spoke English), when all of a sudden, the guy I'm with starts beating the other woman up! What the fuck right? I'm not talking anything playful. He was full-on punching her.
I of course stormed out, trying to get the girl to come with me...but I simply couldn't convey my meaning. I mean, can you imagine how frustrating it was that the worst thing I could call this guy was baka (or "fool")?
When I told this to my Tokyo friend, he finally taught me kusottare. Heh.

The next word is...しりがる。