Toumei Datta Sekai (It Was a Transparent World) by Motohiro Hata

Finally I’ve found it! For those of you who don’t know, this one’s the song used as the 7th opening theme of Naruto Shippuden. I’ve had this very bad LSS that was worsened by the fact that I can’t find a full music video of Toumei Datta Sekai way back then. Great song. And it’s even greater as it was used for the Death of Jiraiya and Pain arc in Shippuden