The other day I reached for some saltine crackers and found myself smirking at the name on the package: "Mornin' Cracker." This interesting name the manufacturers had chosen for their product sheds light on the unique fascination many Japanese have with speaking "natural" English. The Japanese study English for an average of six years yet know what's being taught to them isn't a living, breathing language, and some students go out of their way to use relaxed pronunciation words like "wanna" and "gonna" instead of "want to" or "going to," which are far more natural for a Japanese person to use. As a learner of Japanese, there was a lot of temptation for me to use slang I picked up reading manga or heard others using, but often I found that this lowered people's impression of me. When learning a foreign language, it's best to go slowly when trying out the fun but potentially offensive slang terms you come across, and always watch the Japanese people around you to see what kind of reaction you get. Oh, and it's best not to pick up too much Japanese from Fist of the North Star manga...just trust me on this one.
Popin' Cookin' is another example of the Japanese trying to use natural English, brotha.