What come at Sunny and the others as they walk through the Night Runner Forest?

As Sunny and the others are walking through the Night Runner Forest, a group of bats fly overhead and start smacking Sunny and the others. Orlu tells Sasha to make a high sound and the bats flee or drop dead. They look for Chichi, and they find her with a wound on her forearm. Chichi says that the bats were a bush soul and she slashed it with her juju knife.