When writing a novel, how can a character be developed well, but QUICKLY?

“I know! That’s why I’m putting them under you!”

“Number one, it’s not porn, it’s ecchi, and number two, why would I waste a perfectly good Saturday doing anything else?” Claire pulled at her tea and sighed. “The only thing that could make this day better is if you'd come home with some cute boy, so that after you kicked him out tomorrow I could live vicariously through you.”

Doing something they enjoy, that expresses their personality, and that is in some way unusual or noteworthy;

Why Adding More Bananas to Your Diet Could Impact Your Blood Pressure - Prevention

After Eunice and I finished London Under Veil, I entered the first chapter in a contest at a convention where you could submit something and have it critiqued by a professional book agent.

“You need some tea!”

“No, about the cat. You don’t need a cat. You remember what happened to your spider plant, right?”

What breakthroughs are happening in foundational models of artificial intelligence (AI) in China?

Essentially, what you do is show the character:

“Tart!”

“Yuuna and the Haunted Hot Springs!” Claire turned the book around.

Since when has Taylor Swift become a political journalist? What are her qualifications to recommend candidates for office? Johnathan Swift, maybe, but not Taylor?

They both burst out laughing. “I’m right, though,” Claire went on.

“I’ll put the kettle on.”

Here’s how we presented the character Claire when she was introduced, which the agent particularly singled out:

NY Federal Reserve finds a 'significant share' of companies saying they raised prices on goods not affected by tariffs - Fortune

May studied the black and white comic panels. “Oh, my. She looks…anatomically implausible. What is she doing to that poor man? Wait, are those cat ears?”

“You don’t need a cat. You can’t take care of a cat. You can’t take care of a ficus.” Claire flopped on the other side of the sofa and wriggled her feet beneath May.

“No way.”

S&P 500 scores best May since 1990, but stocks end month with fresh tariff worries - MarketWatch

The agent had only one bad thing to say (the synopsis was crap; writing synopses is hard!), but praised the characterization and particularly how well we introduced a character’s personality quickly.

Do that and you can ground your characters quite quickly.

“It’s a cat. All cats are weird.” May sipped from her mug, inhaling the warmth. She closed her eyes. The room spun. She opened them again. “Ugh. I think I drank too much.”

I am still studying engineering. I feel worried being an average student. Can I get a good job in placement, buy a house, and a car? I don't know why I feel this.

“Nary a cute boy in sight.”

“Why is that always your first suggestion? I do not need some tea. It’s three o’clock in the morning! If I have tea, I’ll never get to sleep.”

“Well, maybe if you’d wear more clothes, they wouldn’t feel so cold. Hussy!”

First look: The new Pedro Pascal-narrated space show in NYC - Time Out

“I need to do laundry.”

“Yes way. It’s washing itself under the street light. Uh-oh, I think it spotted me. It knows I’m watching it. I swear it’s looking at me.”

“Exactly.”

What is the best way to keep my vagina clean and fresh?

“So you didn’t meet any cute boys at the club tonight?” Claire called as she bustled about the small kitchen.

“I try not to, but thank you for reminding me. I know I don’t need a cat. I don’t want a cat. What would I do with a cat?”

“May! You’re home late! Early, I mean. Well, I mean, it’s early in the morning, but you’re home before I expected. Er, after. Before?”

Want to lower your cholesterol? Try a daily cup of this common bean - The Independent

“Fine.” May collapsed into the warm spot Claire had just vacated.

“But they’re cold!”

“They are! He broke the rules of the boarding house by petting this character while she was in cat form, so they invoke the ancient rules of single combat via ping-pong, and—”

Do you wear tights for warmth or to make your legs look better?

“I’m serious!” Claire said. “It’s staring straight at me.” She let the curtain fall. “Weird.”

“Exactly.”

Claire sat back down, legs tucked elegantly beneath her. “You are looking a bit sloppy,” she said, inspecting May through narrowed eyes.

Athletics' Denzel Clarke leaps over wall to rob Angels' HR for incredible catch - ESPN

“Cute girls?”

Create a context between this character and other characters.

“Hang on, are they playing ping-pong?”

“I’m just a fan of your catch and release program.”

“I don’t know. Partying. Going to a pub. Anything besides sitting on the couch reading…” She squinted. “What the hell are you reading?”

“Thanks. You’re looking pretty ratty yourself. Have you been in that bathrobe all day?”

May yelped. “Hey! Your feet are cold!”

“I’m glad my sex life is so entertaining.”

“Well, maybe if you didn’t spend all day reading—” May prodded the book with its garishly-coloured cover with her foot. “Bizarre comic book porn…”

“None of those either. Look upon the wasteland that is my sex life, and see that it is barren. Naught but a moggie followed me home.”

In the kitchen, Claire set out a battered pair of mugs: May’s black, with “PEBKAC: Problem Exists Between Keyboard and Chair” in white letters; Claire’s white, with “This must be Thursday. I never could get the hang of Thursdays” in dark blue. She carried both mugs into the living room. “A moggie followed you home? Is this some weird Internet slang I’m not current on?”

“Claire, I—”

“About wearing more clothes? How am I supposed to catch any fish if I don’t show off the bait?”

May pushed Claire’s feet away. Claire rose to peer out the window. “Huh. It’s still there.”

“Damn straight. So get to it! This time next week, I want to hear some moans coming through that wall.”

Engaging in conversation that also shows something about their intelligence, personality, wit (or lack thereof); and

“Perv.”

“Yep!” Claire chirped. “There’s this schoolboy, see, and he’s homeless, so he lives in this boarding house that used to be a hot springs bathhouse, which is cheap because it’s haunted, so he decides—”

“Nope, I mean a cat followed me home. A black cat, to be exact. All the way from the club. Probably still out there, for all I know.”

“It’s not looking at you.”

Claire, one of May’s three flatmates, former university roommate, and best friend in all the world, shrugged expansively. “It’s a Saturday night. What else would I be doing?”

“You know what? Never mind,” May said. “I am way, way too drunk to be having this conversation.”

“Claire! Why are you still up?”

“From the look of you, if you try to sleep now, you’ll spend the next three hours hanging onto your bed trying to stop the world spinning. Since you’re not going to sleep anyway, you might as well keep me company.”