Ah that was really sweet. Her spirit went to the shrine. I guess because that was the place of the incident? I think I missed that part.

I'm rereading this now and i only just got the 'mary-san' refrence

Until they said her name I thought the ghost girl was Ayumi from the other 3 chapters in this collection (if she had died in middle school). Glad that's not the case. This was super wholesome.