Severus shook his head. "It's only been a day." The tone of voice suggested that Severus had hoped for quick results. He was a brilliant wizard, but no one could manage to master a form change as complicated as that over night. No matter how much they really, really wanted it too.

He was going for bat. The books he read told him that it usually didn't work like that, but it didn't stop him from trying. Like a Patronus, the form was more internal than it was external.

Even so, Severus had hopes of being able to fly into the rafters and get tangled in Black's hair.

"One book says to clear your mind of anything but an animal form. Another says to study anatomy books..."