This is my favorite japanese song.
I especially like the lyrics of this song.

"Kaze ni naru hi" means "a day you(or I) become a breeze".

*Last lines*
yagate kitto so kitto, towa wa setsuna ni satte.
dakedo zutto ah zutto koko ni ite ageru
tada kaze ga fuite iru.

There is no such time that lasts forever.
But I will be always here with you.
Do you feel the breeze around you?

This song may be a very sad song, losing someone very important to you.
But very weird, happiness is the only feeling I get when I always hear this song.

Enjoy! (less info)