What you minored in really is not going to be important enough to change your career path in any way.  Nobody will care whether or not you minored in something that was related or useful.  Just do something you're interested in, like Japanese, and don't worry about it.

I could write you my whole life's story, but I'll refrain. Suffice it to say that I have been teaching music and Japanese in an American public high school for 20 years. The two skills have worked very well for me--when I get tired of one, the other gives me energy. As far as combining the two, I have taught a good share of Japanese folk songs to my music students over the years, and my Japanese classes also do a lot of singing.

But, by keeping Japanese and music in fairly separate compartments, I have been able to sustain interest and energy and I'm quite satisfied in my career choice. Of course, it's not like my one-time ultimate goal of teaching music in Japan. That just didn't pan out for me for a number of reasons.

Outside of academia, I have used my music skills in many public performances. I gig a lot. I use my Japanese skills mainly as a host and guide for exchange students whom I accompany to Japan every summer.

Anyway, feel free to e-mail me if you want to talk further.

Mark