"Sen no Yoru wo Koete" is performed by Aqua Timez and the ending theme for the first Bleach movie entitled "Bleach: Memories of Nobody," which in my opinion is the best of the Bleach movies.  The song's title roughly translates to "Passing Over the Thousandth Night."  The lyrics of the song depict a person who is in love with someone, but is not sure if the person that that person loves feels the same way.  The love could be one-sided, but the person is fine with it as that love is cannot be changed by anyone else and that the feeling of loving someone is fine in itself.  It goes very well with the theme of Bleach: Memories of Nobody as without spoiling too much of the movie, it features a shinigami named Senna and stuff happens such that Ichigo has to go save her.  I guess you can see where this is going.  For anybody that has followed Bleach, Ichigo is one of main characters where he has accumulated a harem  somewhat without his knowledge.  For some reason, girls like him.  It's not an obvious harem like in other series like Negima, Love Hina, or The World God Only Knows, but a number of girls have taken a liking to Ichigo over the course of the series.  In any event, it's amazing that I picked this song over many of the OP/ED songs from the series itself as although the Bleach series hasn't been great of late, it did have great music.

Sen no Yoru wo Koete English Lyrics