It's said that anyone who sees a "doppelganger" will die between about six or twelve months from then.

Some say it's a hallucination seen by patients with mental illnesses, some say it's actually a very real youkai deceiving people.

But in any case, with Suzunaan involved, I guess it only makes sense for it to be a youkai.

He rented it, but he wasn't home.

However, I saw him walking on the village bridge this afternoon. Speaking of which...

...Did Tatsuho read that book?

But the book claimed that the reason for seeing a doppelganger has to be some sort of mental illness and denied the possibility of a youkai.