.. Poe and Lovecraft

Talk to them. You need to talk to both of them. Talk with them until Poe says that Blyton took the book.

Go ask Blyton, in children section, if she took Lovecraft's book. There ought to be more scarier book around here than theirs. Try to find it.

Doris, the librarian, was reading a trashy novel. That's scary...

Give the trashy novel to Poe and Lovecraft. That will settle their fight.