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

“I’ll put the kettle on.”

“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.

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

I've never read the book. What did Dorian Grey do that was so immoral and sinful?

“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 need to do laundry.”

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

What is world history that not many people know about?

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

“But they’re cold!”

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

What are the different celebrity lists (A-list, B-list, C-list, D-list)? How does one become a part of these lists and move up or down in status?

“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.”

“Claire! Why are you still up?”

“It’s not looking at you.”

If you get a chance to have sex with either Kajal Agarwal or Samantha, who would you choose and why?

“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?”

“Exactly.”

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

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

“Exactly.”

“No way.”

Why do wokes use words like "homophobes" when they don't know what that means? Do they realize that no one is afraid of them?

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

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.

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

Can a mother forget her child after she puts him or her up for adoption?

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

“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—”

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

What is the experience of wearing a school uniform every day? Do people typically get used to it or dislike it?

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

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?”

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

Are LGBT people accepted in Japan?

“You need some tea!”

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

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

Are today’s baseball pitchers faster than a few years ago, or is it that radar guns have improved and get the pitch speed as it is released rather than as it reaches the plate?

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

Do that and you can ground your characters quite quickly.

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

What exactly is the difference between a surge protector and a fuse? Can a fuse protect the electronic devices from lightning instead of surge protector?

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

Essentially, what you do is show the character:

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?”

Can a twin flame runner be happy in a karmic relationship?

“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.”

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

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

Why do people turn a blind eye to bad behaviour if someone is very good looking? Whereas if someone is ugly, they get harshly judged for everything?

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?”

May yelped. “Hey! Your feet are 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—”

“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…”

“Nary a cute boy in sight.”

“Perv.”

“Claire, I—”

“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?”

“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.”

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.

“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.”

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

Create a context between this character and other characters.

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

“Cute girls?”

“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.”

“Tart!”

“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.”