Kugayama Shiori

A ghost girl (presumably a high schooler) who's missing all her memories except for her name.

She wants to pass on, but it just doesn't work out, so she keeps casually killing herself, hoping the next death will finally be her last.

Perhaps she' simply forgotten something, an attachment that still keeps her here.
She teams up with the protagonist, whom she meets by chance, to investigate incidents involving women, recreating their deaths in hopes of reclaiming her past.