"I have one more question, Mr. Bones." After calming Professor McGonagall, Dumbledore turned to Su Er.
"Please forgive an old man's concern, because in the Wizarding World, besides the Patronus Charm, there are other, dark spells that can kill a Dementor."
Professor McGonagall had clearly thought of something, and her expression shifted.
Su Er knew he had to give the two professors a demonstration now.
"Of course it could only have been the Patronus Charm, Professor." Su Er took out his wand and recited the incantation.
He summoned his Patronus, though it was only a faint image. The magic required for a corporeal Patronus was rather immense for Su Er at present.
What he summoned now did not display enough power to kill a Dementor, as it had on the train.
But this proof was enough.
The little silver-white badger circled the small room once, then slipped back into the tip of Su Er's wand and vanished.
"Very good, Mr. Bones." The wrinkles on Dumbledore's face relaxed, and a hint of a smile appeared at the corners of Professor McGonagall's mouth, too-a rare sight for someone whose stern image was so firmly fixed in her students' minds.
"I learned this spell from Professor Flitwick last school year," Su Er explained naturally before Dumbledore could ask his next question. "Er, of course, Professor Lockhart also gave me a little help."
"Gilderoy?" Dumbledore raised his eyebrows.
"Er, he gave me a note allowing me to borrow books about the Patronus Charm from the Library." Su Er had cleverly changed "a hundred million" to "a little." Different words, different meanings.
Dumbledore nodded thoughtfully, gave Su Er an inscrutable look, then smiled.
"To learn the Patronus Charm and give it corporeal form as a third-year student-your talent is far greater than I imagined, Mr.