"Is the soap better than ordinary soap or is it just soap?"

"It, uh, gets you cleaner. What a waste of mana. Jiang Cheng worked hard to get me that mana, you know."

This does potentially seem like a waste of mana when you could just make soap. "I'm sure the skills we'll learn will be useful."

"Step one. Cabinets. I hope no one used up all the lye before us, I really don't want to figure out how the potash instructions work."

Okay, that would be bad.

She goes up to the cupboard and opens it like it might try to bite her.

"Guy with the sword and the combat affinity opens the cabinets."

And she was correct in her assessment and is sitting back down.

"It's okay, si-mei, we can follow him."

She nods.

...and carefully hides behind Lan Wangji.

Lan Wangji inspects the cabinets carefully and says, "Clean."

"Oooh, aqua regia, we should keep that-- and gum arabic, that's useful-- quicksilver!"

"No quicksilver."

"Awwwwww."

"I think mercury soap would be bad."

"I wasn't saying we should use it for the soap. Just for future projects."

"Right. That makes sense."

They should probably keep things in the cupboard for people who need it later? That seems polite? But she isn't going to say anything about that.

"Safety equipment," Lan Zhan says, taking four sets of goggles.

"Lan Zhaaaaan, I don't need safety equipment, I'll be fine."

"Yanli."

"Thank you," she says, taking a pair of goggles. Gotta protect your eyes from chemical splashes. Safety first!

He likes this girl. She is a Good Influence.

"I think we managed to get the very last of the lye," Jiang Cheng says, as if the previous students who also had to make magic soap had all personally offended him.

"Read the safety precautions first."

"But--"