And then a boy walks in.

The animals in the shop do not react very well to this event. They don't actively try to murder the boy, because they're in cages and also much too dignified to disturb their cages, but they do look like they would, if they could.

The boy seems unsurprised and resigned.

The shopkeeper, a rail-thin man of middling age, does not seem too pleased 

"Young man, please refrain from disturbing the animals. The poor creatures are unaccostomed to hooligans trampling around their home." 

"He's only looking, maybe one of them will like him."

"Animals hate me," he explains with a soft sigh. "I was hoping magical ones wouldn't..."

They do.

"We'll find one that does!" 

He runs over to Sadde.

"Do you like small ones, furry ones, funny ones, scaly ones?" 

His mother trails behind him, glancing at some of the more exotic creatures with undisguised bafflement.

"I dunno, I haven't really had much of a chance to find out."

A woman walks into the store then and follows the animal commotion towards the boy.

"Here, too, huh, baby?"

"Yeah. Oh, by the way, I'm Sadde, and this is my mum Laura," he introduces to the boy.

"All animals hate you? That's utter nonsense. Here, I'm sure we have something..."

"It's nice to meet you. I'm Melissa, and this my son, Scott."

When elbowed by his mother, the boy turns from the selection of rats to Sadde and Laura.

"Hi, I'm Scott. Good to meet you."

He sighs and follows the shopkeeper who wants to show him animals. "Good to meet you, too."

"Indeed a pleasure."

It's a rather large selection!

Do cats like him? Rats? Glowing rats? Colorful rats? No rats at all?

Toads, salamanders (they're charmed, Madam, don't worry at all), puffskeins, tarantulas?

Nope. Cats hiss, rats scoot, toads croak, salamanders hide, puffskeins turn around, tarantulas make clicking noises.

"What if you stand next to that boy? The animals seem to like him well enough." 

Indeed, the rat who he has apparently taken a shine to seems to be getting along with him just fine. 

It does not get along with this other boy, who sighs.

"I'm sure he'll like you when he gets to know you."

Scott pets the rat.

"Scott, honey, maybe you could try a cat, or an owl? Maybe one of those poofy things?"

"You don't like him?"

"He's very easy to handle, and even with the cost of food added, he's still more purse-friendly than any of the larger animals..."

The shopkeeper is likely concerned about selling the rats, as the sign advertising a sale suggests they don't usually have students clamoring to buy them.

"As long as you promise to take care of it...fine, we'll get the rat."

"I wonder what I should name him. What do you think?"

He turns to Sadde, who only gets a mild hiss from his new pet.