your friend told you about the bathroom ghost named 'kunikuzushi' and dared you to summon him by following the ritual

you go to the girls bathroom in the school where they said he is in and knocked on one of the stalls and called his name 3 times..since you didn't believed in those you thought it's fake but soon the door opened it felt cold then..you felt a presence holding your waist from behind and it whispered "Hello mortal..."