I know it may not be the popular answer but smells. We never know how things smells like and I find that adding this touch anchors me into a place more realisticly.

Speech patterns. Maybe they have a catchphrase, or a favorite swear word. They give everyone a nickname, or they answer questions with questions.

Those that are portrayed as morally bound to their own particular ideals. Regardless of the ideal

How a knight gets in and out of their armor!

That's a detail I always dee overlooked. Plate armor especially is downright impossible to put on by yourself, depending on the make and style. Showing how someone gets in and out of their armor makes the world feel more real to me.

There's a part in my fantasy story where a girl from a royal family (Neserei) becomes friends and starts spending lots of time with a homeless peasant girl (Lara). At one point, Neserei's stockings go missing. It's assumed that they somehow just blew off of the group's (they are in a group of friends) makeshift washing line until Lara is seen wearing them while asleep. The rest of the group forces her to take them off that morning, but she continues to steal them most nights until Neserei manages to get her a pair for her own once they return to her palace.

Lara steals the stockings simply because she likes the way they make her feet feel warm and cosy at night. There is no relevance that this detail has to the larger story. You could take it out and nothing would change.

It's things like this which I think make my characters feel more alive than they would otherwise.

Edit: Just to clarify, these are medieval stockings, also called hose. Not modern day stockings.

https://preview.redd.it/obgirr30qf8g1.jpeg?width=766&format=pjpg&auto=webp&s=9d4f756b7d70e72b265da4023392b90f725f9e8d

Made from cotton. Much softer and warmer.

Hearing their thoughts about what's going on around them or events. Like they can be talking to someone but if a thought pops up in their head like is the person they are talking to is lying or what they aren't saying, or really anything about the current moment makes them feel more alive as it shows the world has influence on them and that they actually think about things rather simply being a vessel for the story.

Contradictions, irrationalities and inconsistencies in their behaviors and beliefs.

Unique interactions that aren't seen otherwise and that may nake you deviate from the norm.

Many things are as simple as they come with a lot of fantasy worlds, for example dwarves and elves hating each other, but the reason most often given that dwarves take too much from nature can be given to many other races,so perhaps make elves hate everyone equally and openly? Like stories of elves coming at night to take away evil children that hurt nature too badly

Or maybe make dwarves be hated universally because they are just that destructive of their surroundings?make their cities reflect a really early industrial age metropolis with people either dying from lung cancer or working long hours and having weird movements because of that.

Also,since it's a fantasy world make their bodies reflect a bit more what they are,like,make dwarves' skin leathery because they work rough jobs often and make elves more animal-like because that way they are better at relating to animals,maybe give them some plant features too?

A single motive for things is boring and too straightforward when life tends to be a bit more complex or extreme,or if you're gonna make a species one sided at least make them an extreme of that side,making their reality reflect what they are and develop into is the ideal point.

When they talk about something small. Be it food, eye catching beauty, clothing.
Paired with Unique speech and phrases. Even if its hailing a god or cursing.

The food

The actual difference in cultures and people

How they treat individual people. Show that there's some history with a certain official/noble figure but not all of them. Let's hear their voice take on a certain tone when news of a warlord comes along the wind. Maybe the main crew visits a kingdom and one of them has just a little too much to say about who they're supposed to meet with for information, before we even know how they look, but they laugh up the rumors towards someone else.

Nuance and adherence to culture.

The police officer that turns a blind eye when a mother steals to feed her child, but ruthlessly tracks down smugglers and vagabonds.

I want to read about a drow, that's actually embraces the culture with a nuance towards reform.

When the character is the narrator and uses phrases and vocabulary appropriate to who they are.

Mine is a musician. So she has album arcs. There are aspects of the story that feed into her actual lyrics. The lyrics literally depend on the unfolding of events to move the story forward. She has actual chart positions. There is a record company she is a part of (her husband owns of). There are other artists on this label and they all have back stories and interconnected worlds. Obviously hair color eye color and texture. Accents and speech patterns. Quirks and romantic fetishes.

Knowing what a character is afraid of is a big one. It's even better if it's not plot relevant, like, bees or heights or something that can come up rarely. And giving them foods they don't like is also a good one. Knowing the elf doesn't like mushrooms, or the dwarf can't stand mint gives them an extra little bit of personality that makes them less of a prop and more of a person.

There's no one thing you can use to reliably give a character verisimilitude. Trying to develop a character as if there is, I think, is a very good way to end up with the exact opposite. Ultimately, making a character that feels "real" is a difficult thing that requires a lot of thought. It's a whole process.

A good entry point to character, creation, I think, is this video by the individual formerly known as "Local Script Man." In recent times, they seem to have either been hacked or honestly just gone of the deep end on their own. I really just have no idea what's happening with them right now, but that video is honestly one of the best I've ever seen on the subject of character creation.

When there are mythological stories, creatures, etc within the setting.

Legends, and lives of common citizens

If we are talking about different races, then details about their biology and things about their daily routine.

If we are not talking about that kind of stuff, then it is the way they interect with their surrendings. How the world shaped them (their look, belief, actions, experience etc), and how they effect the world around them in return.

And most importantly, a lot of pornography and author's barely disguised fetish.

Flaws make characters feel alive. No one is perfect, so having a character that's a little messed up makes them relatable.

For example, my main character Harper hates forests due to unresolved trauma from his childhood. When he has to go through one, he sticks close to his companions and panics when he loses track of them.

It's hard to put the finger down on it. It's the little things. When they act like real people I know. That could even be something small like having inside jokes with their friends and partner, having little rituals in their daily and family life, the way they talk and act etc...

Also from the pov: when they reflect on what's happening around them and their thinking and speech patterns etc. are clearly painted in their own personality. It couldn't be something else pov.

Pettiness, foolishness, or bugbears that only make sense to them & are consistently invoked throughout the story. Real people, all throughout history, have been neurotic & particular, & far too much fantasy stuff makes people too locked in. Common folk & ruralites are often written way too simple to be real, accepting everything as it is & never being neurotic or weird unless that IS their character, & high-society types & nobility are often either cartoonishly prim or overtly flaunting good taste & manners. You need to balance social class markers with individuality.

Giving them connections outside of characters relevant to the story. Give them a sibling they’re fighting for, a friend they see when they aren’t doing something important, a lover, etc. Having background characters can enhance the side and main characters a lot in a story. Not everyone’s going to be or is important.

Seeing how they react. How a character reacts not only informs what kind of person they, but having a wide range of emotions and reaction make them feel like a real, fleshed out people, be they exaggerated or subtle.

There's a centaur I'm writing about that likes to collect things. Whether it be small coins, bottlecaps, or usable trash like thrown away pieces of paper.

A healthy aversion to violence.

Most people, including those who can and have hurt or killed in self-defense before, don't want to hurt other people, simply because it feels wrong to most people.

I like to make it relate to each race’s specific trait

The protohuman are a much larger and stronger ancestor of modern day human. Beside their height ( 8-12 feet tall ) is their enhanced respiratory system and olfactory nerve giving them extremely sharp sense of smell. As such most of them personally brew their own perfume. A perfume tells a lot about yourself or what your mood currently is, meanwhile the more introverted prefer not to use perfume or the most basic perfume possible.

A perfume used in daily life is usually pleasant or light with a unique hint that differ between individual.

While the perfume used by soldier are intense, but not smelly to be able to identify each other from far away. Protohuman are considered the apex species of the time so they have no fear of being tracked by their own perfume. While their military are not organized they still have a basic hunting ( prey and enemy aliek ) group with each group member’s perfume using the same key ingredient so their individuality and their group unique smell are identifiable

Not using perfume is socially acceptable but it is akin to keeping to yourself. Not showing any expression for others to see unless required like in the military. Because in the end, the reason they started using perfume in the first place was to soothe their super sense of smell. The rest come after

I have a fantasy story, where one of the main characters was a disgraced officer who survived a horrible ordeal in a battle. In his quest to try and redeem his honor, the field marshal sends him on a series of mission that have him go around various continents known as "worlds" - magical sea storms separate the continents for some reason. Throughout his journey, the officer and his men take from the cultural societies they have encountered from food to clothings to give comfort during the colder weather.

Being wrong about things in the setting’s lore that aren’t secrets. Like, this guy thinks Aronor province is next to Khilae. Or this guy tries to talk about magic but has to give up when she gets beyond her knowledge. This also allows characters to bicker about this stuff like real people. Like that Calebcity sketch about the “entire state building.”

For that matter, talking about things/doing things when they’re lying in wait/working on something/nattering/bored. Like, the party’s archer rolls an arrow in his palm sometimes. Someone looking out the window. Details that show people aren’t automatons, and aren’t 1000% locked in 24/7.

The things they do when not speaking. And I don't mean fighting. I mean all the fidgets and postures and gestures and idiosyncratic behaviors that don't add much to the plot, but do tell me what it's like to be in the room with that person.

I don't know if have original characters and they work at the dream factory helping monsters build dreams for people in the matrix and the main characters are supportive and great and smart and patient.

What they reflect on or admire in their life. Past events that inform their character, or their relationship with another. At the end of the day like real life, characters are constantly meeting and colliding and integrating with others and these positive or negative relationships do make us who we are to an extent. It just makes em feel more like a person.

Que no todo gire entorno al protagonista, sino que se muestren sucesos a parte de la trama principal. Eso le da más amplitud al mundo.

También que los distintos lugares tengan sus características, ya sea por la cultura o la geografía... Y que estas tengan cierta relevancia en como se encamina la historia.

Por último, que los personajes secundarios interactúen entre sí sin necesidad de un protagonista que haga siempre de pegamento en el grupo. Que no estén callados cuando el principal habla como si solo existieran para escucharlo, sino que mientras él conversa, los otros hacen sus asuntos.

I like giving simple traits like "they're a good cook", "they can quickly get annoyed" or "they can be a bit naive". It's not what defines them, but it's part of their character nonetheless. Another thing I like giving my characters is a favorite food. You know, like sometimes in the story they come across their favourite food and they get excited about it.

These are simple things that I feel like a majority of people do, but I still feel like their important

Hobbies and interests. Specifically ones that have little to no bearing on the story. I find giving my characters 3-5 hobbies or special interests, some that go hand in hand (say reading and writing) and some that contradict each other (say painting and science), makes my characters feel so much more alive and in depth. It also gives them something to bond over, especially when multiple characters share the same hobby/interest, and is a good way for them to connect and therefore develop deeper relationships, especially when they start as strangers.

I have a knight and a guardsman who had a habit of making really stupid bets when they were teenagers/young adults.

My knight once smuggled a bottle of white liquor to the guardsman when he was in the infirmary and they hid it under a loose paving stone so the healers wouldn’t find it.

My guardsman is now a recovering alcoholic, who lives in a realm whose primary industry is wine making, which limits what he can and can’t drink. This makes navigating feasts, banquets, religious ceremonies and his own wedding day hard to navigate