Ju-ken is a Japanese session bassist. He was a support member of Gackt, Vamps and Anna Tsuchiya. He is one of the most in-demand bassists in Japan.

"Love Letter" is a single released by Gackt on March 1, 2006 under Nippon Crown. It peaked at ninth place on the Oricon weekly chart and charted for seven weeks. The A-side and B-side were used in the