An everlasting Haunt
If I were Keiko I would have made it my mission he never was happy, never had joy, and made sure he never found love! Haha, I would haunt him till he wanted to jump out a plane without a parachute and kill himself XD!! Or at least make him go crazy like Sally did to her ex fieancee in Being Human.
KEIKO THE UN REVENGEFUL GHOST >:D!!