The opening song to D.Gray-man is INNOCENT SORROW by abingdon boys school. For those of you who don't know, a.b.s. was formed last year by Nishikawa Takanori (aka. T.M.Revolution) and people he's worked with (SUNAO, Shibasaki Hiroshi, Kishi Toshiyuki). And yes, the Abingdon School does actually exist. INNOCENT SORROW is actually the band's debut single, although they have recorded a few songs previously (including stay away on the LOVE for NANA album that I love).