I have no memory of standing up going into the kitchen and turning the tap on for no reason why would I do that. Maybe it's water pressure building up inside the pipe which then sort of forces itself out of the tap maybe water which is left in the pipe just coming out but the pipe was open. Another theory is maybe I did it myself in my sleep you know because sleepwalking is is thing that happens. The belief in ghosts and ghost stories is quite common in Japan according to an old woman who used to teach me about this subject.