Natsume is at home early one evening when he hears a knock on the door.  He sees Tohko outside, asking to be let in.  But when he opens the door, there's nobody there, and a gust of wind rushes past.  Another Youkai is after the book of friends!
but it might be something 
that Youko-san left for me.
pero podría ser un sobre 
que dejó Yoko-san.
pero podría ser que este sobre lo hubiera dejado Yoko-san.
mas pode ser algo que a Youko deixou para mim.