I think Sho was supposed to swear a lot in the Japanese dialogue. They never go any worse than "shit" in the English P4AU, so Sho ends up saying "shit" a bazillion times. I make fun of it a lot when I play P4AU.

For example, he says something along the lines of "I'm sick of this shitty world with it's shitty people and shitty lives!" or something.