As Harry, Ron, Hermione, and Neville made their way down to Hagrid's - Harry had gotten the note inviting him during their free afternoon, and the others had decided to tag along after what, to Ron, seemed like a very odd Potions class - they were startled but unsurprised as Harry was all but tackled to the ground by an exuberant squirrel girl. "Hey Harry!" Penny greeted excitedly as she snuggled into him, he responding in kind as soon as he gathered his wits much to Ron's amusement, Neville's uncertain confusion, and Hermione's quiet approval. "How was Potions class? I know Fred and George were warning you about it, but Professor Snape didn't seem so bad to me..."

"It was odd," Ron spoke up before Harry could. "It looked like he was going to be picking on Harry right at first, but then..." He shrugged, uncertain how to express it.

"Other than the first comment about Harry being the 'new celebrity', everything he said to Harry was really neutral in tone," Hermione pointed out thoughtfully. "He was certainly strict and a harsh taskmaster as a teacher...but considering what nearly happened with Neville's potion, I guess I can't blame him with how dangerous mistakes can be in that class."

"Yeah," Neville offered awkwardly. "I nearly put the porcupine quills into my potion without taking it off the fire-"

"Oooh, that would have been bad!" Penny pointed out with a wince. "Porcupine quills are used to add softness to things in Potions, so you have to be very careful how much heat they get and at what rate. Putting them into a bubbling potion while still on the fire would have spread the softness into the pewter of the cauldron and it would have melted, spilling over everyone and everything there. Not to mention if the potion was incomplete, that would have likely resulted in the opposite intent of the potion you were making..."

Neville's eyes widened. "We were making a boil cure...I'd have been covered in boils..."

"So that's what he meant when he said my logic and answer was right but my reasoning was flawed!" Hermione gasped out in excitement. "When he stopped Neville from doing it, he quizzed Harry on what step Neville had missed, then asked the class to guess what would have happened. Crabbe guessed 'something very, very bad', which Professor Snape said was 'unimaginative, but not inaccurate', and I guessed that because quills on creatures carry a toxin as a defense mechanism, the heat from the potion would have turned that acidic and melted the cauldron."

"Yeah, that's a bit too literal minded with Potions," Penny explained with a smile as she shifted to walking next to Harry with one arm and her tail around him, rather than clinging to him with her whole body. Harry himself had one arm around her and his other hand gently brushing her tail against his cheek. "A lot of Potion work early on is in what the ingredients represent rather than what they actually are. It's not until you get into NEWT work that what the ingredients actually are become significant as the potions get all the more finicky, fixing flawed potions becomes a skill, and even trace elements in the ingredients can have an effect. At that point, the fact monkshod and wolfsbane are regional names for the same plant become important as even where the plant is grown can influence the outcome of the potion."

"Professor Snape did mention the whys of Potion flaws and fixing them were NEWT level work which was why he wasn't explaining them during the very first lesson," Hermione confirmed in awe. "But how do you know all that?"

Penny lowered her head bashfully. "I...used to get in a lot of trouble being rambunctious in my Great Uncle Merry's Potion lab..." she allowed in embarrassment. "So many lectures on Potion safety..."

"Your Great Uncle works with Potions?" Neville asked curiously.

"Potions, Alchemy, Transfiguration, Herbology...he's got his Masters in every subject," Penny replied warmly. "Taught me quite a few things growing up, and crammed a few extra lessons in when he learned I'd be attending Hogwarts. He's a lot of fun to be around, even when teaching." She smiled impishly. "He's a little like Professor Dumbledore, honestly...but more so, if you can imagine that."

"I don't think I want to..." Ron murmured in awe. "Someone even more barmy than Dumbledore...bizarre..."

"A little hard to believe, honestly," Neville agreed as he knocked on Hagrid's door.

There was a sudden scrambling sound, followed by several booming barks. "Back, Fang!" Hagrid bellowed from inside. "No Fang, don't-"

Without further warning, the window of the cabin burst outward as a massive black boarhound lunged straight for Penny's tail, letting out several booming barks that somehow made him seem even larger. Penny let out a startled shriek and took to all fours, the hound chasing after her.

"Penny!" Harry called out worriedly, about to take off after her to try and tackle the dog if that's what it took to stop him.

He was interrupted as the door slammed open and Hagrid rushed out. "Which way?" he demanded urgently. "Which way did he chase her?" Hermione promptly pointed off after the racing pair, only for Hagrid to pale in response. "Bollocks, they're headin' for the Willow!" He then took off in a long, loping stride that soon left the others struggling to catch up.

While Ron, Neville, and Hermione tried to pace themselves to avoid collapsing out of breath so they could actually do something when they caught up, Harry pushed himself as hard as he could and was actually able to keep up with Hagrid's loping stride. All those years of running when Dudley played 'Harry Hunting' actually did him some good as he had learned how to control his breathing when running full out so strain on his lungs wouldn't make him give out before his legs could. He almost pushed harder than he knew was safe anyway as he heard Penny's frightened shrieks...only to become confused as the barks stopped and Penny's cries turned to amazed delight. Hagrid suddenly grabbed him by the collar and pulled him back and off the ground.

"Easy, Harry," Hagrid cautioned in a gasp, plainly a little out of breath himself. "Looks like...things are fine...?" He didn't sound like he believed it himself...and when Harry looked up, he could see why.

The boarhound - Fang, presumably - was sitting on his rump and slowly pushing himself back with all four legs, his tail tucked under his rear as he backed away from the tree in front of him, not that Harry could blame him. The tree looked like a normal willow tree except for a few major differences. For one thing, despite it barley being the start of autumn, the tree had no leaves whatsoever. For another, instead of branches that ended in thin tips like most trees, each branch ended in a thick, knotted sphere of wood that strongly resembled a clenched fist of massive size. For a third, the entire tree was swaying back and forth as the branches lashed about as though trying to punch something.

While this would normally be worrying, those who were watching had a hard time focusing on that given that the tree seemed to be trying to hit something that was racing around in its branches...something that resolved itself into Penny who was looking a bit more squirrely than normal and seemed to be having the time of her life.

"This is so much fun!" she squealed out excitedly as she leapt from branch to branch, sometimes mere millimeters away from being squashed flat by one of the flailing branches, but for all the worry she showed there might as well be miles. "I've never had a climb that changed on me while I climbed! Where do I get one of these for home? How much do they cost? What sort of care do they need? Can they grow even bigger?"

As Penny rattled on about how much she was enjoying herself and wanting a tree like that of her own, Ron and the others caught up and Hagrid let out a sigh. "I'll go get the tea things, we might as well make it a picnic..." With that, he turned to walk back towards his cabin. "Keep an eye on Fang for me, will ya?"