....free coffee? There has to be one hell of a catch, but, against his better judgement, he drifts over. 

"Is the coffee free free or free with purchase?" 

"Chocolate! I love chocolate."

He's going to take a chocolate first and figure out whether it's free with purchase later.

... 

...

...

...

...

is that chocolate

"It's really free. Please don't walk off with my cups though. Nice to meet you three, I'm Lily." (She uses the name of the flower in Mandarin.) "The little chocolates are free, too, and I have more to sell you if you're not content with four measly little squares."

Nobody gives away resources for free in the Scholomance. 

"....What's the catch?"

"Well, I'd appreciate it if you listened to my sales pitch. And if you decide to buy something my cunning plot has worked, and if you don't I'm not out by much. Fair enough?"

Maybe they're poisoned? But that would be awfully ruthless for day one. 

He cautiously takes a chocolate and a cup of coffee. "Fine by me." 

"Is it poisoned? If it's poisoned I'm going to kill you."

This man has an aura of Obvious Maleficer.

...Wen Qing is nearby and he's hungry.

He grabs a chocolate. 

"You know, you'll have a better time with the Mandarin speakers if you have tea."

"Speak for yourself." 

"You will have a better time with me if you have tea. I've never had coffee in my life."

She smiles, just slightly. 

"So, what I have for offer. My affinity is bracelets; they're quite efficient and useful little things. I have two types for spell enhancement - shielding and blasting, each a significant edge - one for endurance, which helps with fatigue, poison and wounds, and then finally mana storage, which does what it says on the tin. All of them have been painstakingly handcrafted over a period of four years, and all the flaws in the designs have been worked out. They are amiable to other enchanted items and generally possess little personality."

"As for luxuries, I have chocolate, cherry gummies, cheetos, chips, spices - have you tasted the cafeteria food yet? Needs a little salt in my opinion - and of course coffee and tea. The mana-heating moka pot is for sale as well. In the school supplies department I have quality mechanical pencils - side-advance so you don't have to click the end all the time, and with good deep erasers that'll last you months - a selection of good metal rulers, and superglue, for all your repair and artifice needs."

She looks at Xue Yang. "'You think I'd be stupid enough to poison a group of random Mandarin-speakers on my first day in the Scholomance? Might as well paint a target on my back and declare myself open season. You will note I'm serving myself as well; if you want me to swap plates with any of the samplers I'd be happy to." 

She nods to Nie Huasang. "Jasmine, Chamomile or Earl Grey? I'm afraid I don't have matcha."

Well, that sure is a strategy. "Thanks for the food. I hope you find buyers."

Time to head back to babysitter duty. 

Xue Yang suspiciously swaps plates with her and then puts it in his mouth.

His eyes widen. 

He mumbles something through his mouth of chocolate that might very well be "chocolate!!!!!"

Oh, he likes this girl. 

"I can make moonshine, I have an extensive supply of pornography, and I draw excellent sketches suitable for decorating your dorm room or wooing your crush."

"Good, isn't it?" 

She pulls out a hundred-gram bar from her pack. It's twice the size of her hand and almost as thick. She sets it on the table between her and Xue Yang.

She looks over at Nie Huisang. "I will trade you a dozen tea bags for three dirty mags at least one of which is lesbian, or for a technical sketch of my choice, or for a bottle of moonshine that's no more poisonous than usual for alcohol. I'm willing to extend you that much on credit."

"Oh, no, I'm going to get in so much trouble if I trade for tea, Lan Xichen is mad that I'm selling moonshine at all, it's bad for the dignity of the enclave. How much for three of those bracelets? We could use those, I'm sure he wouldn't be mad at all about that."

That chocolate is Xue Yang's chocolate now.

It is fascinating how quickly that chocolate disappears down his mouth.

"Someday I'm going to be rich and have candy every day."

That's not what 'rich' means.

"For three bracelets I'd want something on the order of thirty good quality gems. You might be able to buy one for a combination of favours and dirty mags, though. I would want... five dirty mags, two sketches and a bottle of moonshine, for a bracelet of your choice."

She looks over at Xue Yang. "And I do expect you to pay for that bar."

"Oh, I don't know, I don't know, I haven't even made the moonshine yet-- what about three dirty mags and three sketches? Is that okay?"

She considers for a moment. 

"I'll take it. Shielding, blasting, endurance or storage?"

He considers what's going to be easiest to shop around to the enclaves, then says--

"Blasting."

"What if I pay for the chocolate bar by not murdering you?"