Celestia barely spared a glance for the feline Thing that was now purring away in Mr. Yoon's arms. She was still pleased that it seemed to be putting the boy at ease somewhat -- or at the very least, he seemed to like it. That was definitely progress. The Thing had spent most of its time in her custody in a pygmy puff's shape, but she'd been thinking that perhaps it could spend some time as a cauldron when it got too annoying in BOTH shapes. It didn't even appreciate all of the dog toys and nice, comfortable dog bed that she had brought in from her parents' place just for it. Such an ungrateful little thing...

Celestia was so consumed by these thoughts that she blinked in confusion as Mr. Yoon finally got his question out. Oh, Merlin, how to word this? She expected these sorts of questions from students, but hearing a second year express the desire to become an Animagus was a bit of a shock for her. She hadn't even given Animagi a thought until her fifth year!

The professor took a sip of tea and dropped into one of the two squashy armchairs that were close to the fire before she even opened her mouth to speak.
"Why don't you sit down, Mr. Yoon?", she asked him with an encouraging smile. Celestia paused for about a minute to keep gathering her thoughts let Mr. Yoon get himself situated before she continued to speak in a gentle tone: "Becoming an Animagus is a difficult, very serious business. As you said, it takes years to become one successfully and safely. To be perfectly honest, Mr. Yoon, you are only in your second year at Hogwarts." Celestia heaved a long sigh and took another gulp sip of tea. She knew that kids hated having their age brought up, but she didn't want this boy to leave her office thinking that it was okay to take chances. "I think that you will be quite capable of becoming an Animagus when you're older IF you study hard and take the proper precautions. You should not by any means attempt to teach yourself how to do this out of a book or by yourself. Is that clear?" Celestia tried to keep her tone light and friendly, but she was afraid that a note of sternness had crept into her voice by the end of her speech. Sighing, she went on in a determinedly lighter tone, "I'm willing to help you in any way I can when the time comes, Mr. Yoon. For now, I'll give you a few titles to check out from the school library. You should work particularly hard in your Transfiguration, Potions, and Charms lessons if you continue to hold this ambition." As she spoke, a black quill lying docilely on the small table next to her chair stood to attention and began scribbling book titles and authors on a spare bit of parchment. Once it had finished, the quill fell flat on its side once again.

Celestia thought over what she'd told the young Gryffindor so far and frowned at herself slightly, before adding, "But all of your subjects are equally important, of course." She wouldn't want word to get around the school that she had recommended certain classes above others -- even if those three subjects were the most useful ones for learning to become an Animagus specifically. All courses at Hogwarts made kids into better witches and wizards in different ways after all.