I know only very little Japanese (thanks to tagging my music, and constantly viewing only the Japanese characters when picking songs, I learn a bit and can even read some Kanji from that ;D ) and maybe 5 words in Chinese, hah.
Lyrics have never appealed to me, much. There are very few songs where I really.. care what the person is saying. Sometimes I feel like words in songs are cheesy, and that can ruin the feeling of an otherwise captivating song for me. I like to enjoy music for its sound rather than its meaning. But, when I find a song so beautiful, it kind of takes on its own meaning in my mind, just for me. Part of me never wants to learn Japanese, Chinese, or Korean just so I can go on enjoying music like this. Also... Japanese with its shorter syllables just sounds so much better when sung than English does. Finally, one of the best kinds of sounds in music to my ears is slightly higher-pitched, female vocals and that has been easier to find when it comes to Japanese singers in my experience. :)