"Japanese Prison Blues" was sung by Eric Cartman in the Season Thirteen episode, "Whale Whores".
Background
The Japanese government kills Paul Watson of the Sea Shepard and takes Cartman, Kenny McCormick, and Stan Marsh prisoner. Emperor Akihito arrests them for sinking his whaling ships and explains to the boys why his people hate dolphins and whales so much.
Lyrics
Well I'm in Japanese prison Lawd
Japanese prison got me down
Said I'm in Japanese prison Lawd
Don't belong here, my eyes are round.