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

Essentially, what you do is show the character:

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

“It’s not looking at you.”

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“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.”

“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?”

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“You need some tea!”

“Perv.”

“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?”

I am 13 and I am planning to run away. What should I do to succeed?

“Exactly.”

Create a context between this character and other characters.

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

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“No way.”

“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! Why are you still up?”

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“Nary a cute boy in sight.”

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

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

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

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.

Do that and you can ground your characters quite quickly.

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“Exactly.”

“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?”

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

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“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.

“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—”

“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.”

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

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

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

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

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.

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

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

“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.”

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

I want to have anal sex, but my wife refuses. What do I do?

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

“I’ll put the kettle on.”

“Claire, I—”

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

“Tart!”

“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…”

Hello,hope y'all doin good, i came to Quora to share my strange story , a very weird one , a story when luck smiled at me ,maybe u will enjoy it , let's begin,have fun... A year ago ,I was a real porn addicted(btw I was 18) ,but never had sex before, I don't have a gf I didn't try to find one even ,always thinking to go to find a sex worker but then I just don't , everyday watching different bodies getting fucked and everyday enjoying. One day, I was watching porn, a big ass lady with big boobs ,just after seeing her the image of my female cousin poped in my mind, (let's introduce her : she's 35 years old , very big ass , nice boobs ,not very big but nice,always wearing tight clothes , she's divorced ) and I thought of me fucking her ,I never had sexual desires for her but now I do days went by and when I met her I was so horny ,I couldn't stay with the family cz my penis was clearly erected , I realized this is my first time I get horny for one of my family ,it not illegal in my country.well to make a long story short( if u want details just text me I will tell u 😊),I decided to give her signs that I want to fuck her,finally I decided to have sex and with my cousin , I thought it is the best beggining for me, i started touching her when I came across her in a narrow place , make her feel my hard cock when we hug , I thought it will hard and I will be ashamed but no , I felt nothing and she said nothing , probably she thought it was by mistake,anyways, I decided then to talk with her about sex, waited for her to be alone in a room and talk with her, I confessed everything about me watching porn and addicted..etc,she said it's normal and u are growing up and u must have sex,well at that time I was like whaaat????? Well I didn't control myself and asked her for sex ( horny like I Ve never been before) she said that she will think Abt it ,2 weeka went by then she called me ,telling that she reserved a room in a hotel and we meet tonight ,we met,and bruuhh, sex is great , I mean, I had to find a pirstitue ,what I was waiting for to have such a feeling ????, I will never forget that night, I started kissing her she was kissing hard ,she misses sex so bad , she sucked my dick and swallowed my semen ,I felt I'm in a dream , then when fucked ,her ass was very big and the anus was open ,didn't struggle to get my hard cock inside it , she was obviously missing sex , she was shouting ,fuck me yh fuck me , I go fast after every word until I cum , we did that 3 times , then we went to her pussy , using condoms I fucked her so hard the moans were higher , everything was perfect ,in the end I asked her to lick her body , licked pussy ,ass, boobs,then she sucked my cock until we sleeped ,all I know that she was dirty ,well before even having sex with her I knew she is an open minded woman , and a woman that looks that she donesnt know anything , but she knows everything, but never expected having sex with her ,well she was horny and that helped...but no one of us regretted that sex ever.. We still have sex from time to time ,and I started having sex with sex workers , joining threesomes..etc If u want pics of her text me.

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

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

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

“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.”

“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.”

“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.”

“I need to do laundry.”

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

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

“Cute girls?”

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?”

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?”

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

“But they’re cold!”