▁on ▁Earth ▁until ▁it ▁can ▁be ▁laid ▁to ▁rest , ▁either ▁by ▁performing ▁the ▁missing ▁rit uals , ▁or ▁resol ving ▁the ▁emot ional ▁conflict ▁that ▁still ▁t ies ▁it ▁to ▁the ▁physical ▁plane . ▁If ▁the ▁rit uals ▁are ▁not ▁completed ▁or ▁the ▁conflict ▁left ▁un resol ved , ▁the ▁y ū rei ▁will ▁persist ▁in ▁its ▁ha un ting . ▁ ▁O ft ent imes ▁the ▁lower ▁the ▁social ▁rank ▁of ▁the ▁person ▁who ▁died ▁viol ently ▁or ▁who ▁was ▁treated ▁har sh ly ▁during ▁life , ▁the ▁more ▁powerful ▁as ▁a ▁y ū rei ▁they ▁would ▁return . ▁This ▁is ▁illustrated ▁in ▁the ▁fate ▁of ▁O i wa ▁in ▁the ▁story ▁Y ots u ya ▁Ka idan , ▁or ▁the ▁servant ▁Ok iku ▁in ▁Ban ch ō ▁Sar ay ash iki . ▁ ▁App earance ▁In ▁the ▁late ▁ 1 7 th ▁century , ▁a ▁game ▁called ▁Hy ak um on og at ari ▁Ka id ank ai ▁became ▁popular , ▁and ▁ka idan ▁increasing ly ▁became ▁a ▁subject ▁for ▁the ater , ▁literature ▁and ▁other ▁arts . ▁U ki yo - e ▁artist ▁Mar uy ama ▁ Ō ky o ▁created ▁the ▁first ▁known ▁example ▁of ▁the ▁now - trad itional ▁y ū rei , ▁in ▁his ▁painting ▁The ▁Ghost ▁of ▁O y uki . ▁The ▁Z ens h ō - an ▁in ▁Tokyo ▁houses ▁the ▁largest ▁single ▁collection ▁of ▁y ū rei ▁paint ings ▁which ▁are ▁only ▁shown ▁in ▁August , ▁the ▁traditional ▁month ▁of ▁the ▁spirits .