Ron Weasley had a pet rat named Scabbers.
Strictly speaking, Scabbers hadn't started out as his. At first, he'd belonged to Ron Weasley's older brother, Percy Weasley.
But the Weasleys were poor. In a family like that, you wore what your older siblings outgrew. As the youngest boy in the house, Ron Weasley had long since gotten used to inheriting his brothers' old things, pets included.
Ron Weasley doted on the rat. What made him furious was the way his roommates looked down on Scabbers, treating him like nothing more than "owl feed."
It drove Ron Weasley up the wall.
That day, as usual, Ron Weasley brought Scabbers back to the Gryffindor common room.
"Dilligrout," he said, giving the password. The Fat Lady swung the portrait open, and Ron was just about to step through—
When a pure-white owl shot out of nowhere and swept right over his head.
Ron jerked, startled, ducking as the owl flashed past.
That Potter's owl!
As a roommate, Ron recognized the wretched thing at a glance. Potter was always feeding it dried mice in the dormitory, and Ron had never liked the way it looked at his family's rat.
While Ron was stewing, he suddenly felt Scabbers tense in his hands. The rat wriggled free as if frightened, dropped to the floor, and bolted.
"Hey! Scabbers, don't run off!" Ron bent down in a panic to grab him—
Only to have his way blocked by George and Fred, who looked half-dead on their feet.
"What're you doing, Ron…" George muttered weakly, staring at Ron in front of them. "Move. We need to rest."
"Scabbers—my Scabbers ran off!" Ron blurted, frantic.
"Scabbers? Oh, that rat." Fred glanced back, but the rat was already long gone. "Relax. Scabbers is clever. He'll come back on his own."
"Yeah," George said with a huge yawn. "Right now you just need to either get inside or get out of the way. We're exhausted." He turned and complained to Fred, "Why did Leonard suddenly make us do extra practice?"
"Who knows," Fred said, slumping his weight onto Ron and shoving him forward. "Maybe he thinks we're improving too slowly."
They pushed into the common room together.
Inside the castle, the snow-white owl Hedwig beat her wings to slow down, then landed lightly on an outstretched arm. She fussed carefully with her talons, making sure she didn't scratch the person holding her.
In the shadowed corner of a corridor, Leonard watched her cautious little movements and smiled, rubbing her head gently.
"Thanks, little one."
"Hoo!" Hedwig squinted as she called. To Leonard, it came through as perfectly clear words: "You're welcome, snuggle~"
That was what Nature's Friend did. Compared to Friend of Plants, which only allowed simple communication with plants, talking to animals gave clearer feedback and worked far better.
Even an ant had more mobility than a plant, and every animal seemed happy to do small, simple favors for Leonard.
"Alright, off you go," Leonard said. "Your owner is probably about to argue with Ron Weasley. You'd better make sure you can prove you didn't eat the mouse, or you'll get an earful."
He let Hedwig go, watching her linger for a moment before finally flying off.
Then Leonard unfolded the Marauder's Map and followed the moving names as he walked silently to the next corner.
When a name flickered past, he shot his foot out and stomped down.
"Squeak!" A sharp, shrill cry rang out.
Leonard looked down. A plump rat was trapped under his foot, struggling wildly, even trying now and then to gnaw at his calfskin shoe.
"Got you," Leonard said, a faint smile tugging at his mouth.
Scabbers went still, staring up in shock. Before it could decide whether Leonard had seen through it, Leonard snapped his fingers.
It was like a pebble had smacked the rat square on the head. Scabbers went limp instantly.
A snap-cast Stunning Spell wasn't very strong, just enough to knock out a rat.
Leonard bent down, picked up the unconscious rat by the tail, and walked up the empty corridor toward the upper floors.
The plan had worked. He had his test subject.
...
Hedwig, Harry Potter's owl, often wandered around the castle grounds, so Leonard had no trouble finding her.
And with Nature's Friend, earning an owl's trust was easy. Getting her to do a small favor was even easier.
Like scaring a certain rat into running.
In Leonard's plan, Hedwig only needed to keep the presence she had while hunting and burst out at the right moment, just as Ron Weasley returned to the Gryffindor common room. That would very likely startle Peter Pettigrew, who was already dangerously close to being shaped by the habits of a rat.
Then, as if by pure coincidence, George and Fred would come back from extra practice and block Ron Weasley from chasing after his rat, giving the panicked Peter Pettigrew time to flee farther.
That was when Leonard would swoop in and catch him.
It sounded like too many coincidences stacked together, but Hedwig had been arranged by Leonard, and when George and Fred took their breaks was up to him.
All Leonard had to do was time Ron Weasley's return to the common room, and with the Marauder's Map, that was easy.
Honestly, the Marauder's Map was incredible. Using it just to play hide-and-seek with Filch at night was a complete waste.
As for why he'd gone to all this trouble—simple. He wanted to kidnap Peter Pettigrew quietly, use him to test potions, and run a few experiments along the way.
He had no intention of letting anyone find out he was using a person to test potions.
Humming to himself, Leonard swung Peter Pettigrew by the tail as he returned to the Room of Requirement, then casually tossed him onto the floor.
With a sharp "squeak," the unconscious Peter Pettigrew snapped awake. He blinked around in confusion and realized he was in an unfamiliar place.
It still had the feel of Hogwarts architecture, but Peter Pettigrew was certain he'd never been here before.
His eyes landed on Leonard. He recognized him—barely. He'd only seen him once, a student from Hufflepuff, if he remembered correctly.
What did he want? And where was this?
After more than ten years as a rat, Peter Pettigrew was overwhelmed by panic. His mind had been idle for so long, living off scraps and waiting to rot. Faced with this sudden, inexplicable danger, he went rigid with terror.