In 2002 Ken formed his own band, Sons of All Pussys (S.O.A.P.), as a result of a break in L'Arc-en-Ciel's activities, with ex-L'Arc-en-Ciel member Yasunori "Sakura" Sakurazawa as drummer, and Ein as bassist (a half Japanese/German model who appeared in a few L'Arc PVs).
On August 23, 2006, Ken released a solo single titled "Speed", and has taken a new "clean" appearance similar to his early days with L'Arc-en-Ciel.