I watched it out of fucking nowhere on the tv in my room with the lights off, I was like 10 years old. I remember I got clinged to watch this anime because I've always liked the horror genre in general, and I really liked the opening (which by the way is quite cheerful, though, ironical for it being horror anime about ghosts...)
The scariest episode and curiously the very first episode I watched is the one about the living vintage doll, and under all the given, said circumstances, watching the that freaky final scene with the living toys, it was disturbing for 10 year old me.