[SSJup81]

Are you majoring in International Business? If so, you can minor in Asian studies or something like that. With International Business, I'm quite sure it's mandatory to have to take some type of a foreign language or cultural study or a particular country.

That aside, if you become fluent enough, maybe you could work as a CIR (Coordinator for International Relations). I know this is an option through JET (Japan Exchange and Teaching) program, so maybe one can pursue a career in this without the assistance of the JET program or something similar. All I know is that to work as a CIR, you have to be really really really fluent in the language. IIRC, someone here was saying you have to pass at least the level 2 JPT.