Characters can be a mine field. You can make up your own characters or use pre-existing characters (fan fiction) and you are completely free to do whatever you like with their personalities but if the character is well known, people will be more interested in the story if that character is portrays as close to the original cannon personality as possible.
If, for example, you are wanting to take a well known character and switch up their personality on purpose then stick as close to the trait as possible.
A yandere character isn’t going to magically turn caring or understanding so try not to let that happen (unless you have a good reason for the change that’s explained in the story.)
One of my most favourite stories is by biased34 ‘I’ve got you under my skin.’ (Todoroki x Reader x Bakugou)
Both Todoroki and Bakugou are as Cannon as heck, I even suspect Kohei wrote this story under a pseudo name! The author has not changed their personalities to suit the story, she has worked them perfectly. Go check it out for reference 😉
X Reader personality.
Seeing as I am most known for my reader insert stories I’ll share a little about how to detail personalities for a person reading your story.
I think most of my reader personalities are similar? (It’s hard to make a completely different character for each book) but I do try and match the reader personality to the character.
If I’m working with Tamaki Amajiki (shy baby) I’ll have reader be a little more confident and encouraging.
If I’m working with Hawks (Keigo Takami) I’ll have reader be a little more reserved.
For the most part opposites do attract so I try and give them differing personalities so that there’s some dynamic but then there are characters that you just want the interactions to be INTENSE and combative.
Like a Bakugou x Reader with reader being the same type as Bakugou. – that’s a very high energy book lol
Looks and features of characters.
For pre-existing characters I read over wikifandoms page that outlines their looks. If it says they have periwinkle blue eyes, then you can BET I write that they have periwinkle blue eyes lol
For reader insert I try not to detail anything about their looks because people get upset when you get it wrong. (But honestly, how are we, as authors, supposed to know? Exactly. I hear you. But yeah, just best to leave it blank lol)
In the case of x readers it’s best to be as simple as humanly possible. Scrap all of that poetic writing you’ve been aiming for and simmer it down to.
“You rolled your eyes to the side and gave him a dead stare.”
“You rolled your blue eyes to the side and gave him a dead stare, a strand of blond hair falling across one of your round eyes and obscuring your vision.”
If you want an alternative you can always let them insert:
“You rolled your E/C eyes to the side and gave him a dead stare, a strand of you H/C hair falling across your E/S eyes, obscuring your vision.”
For me- personally- the last one is a little disjointed to read because you have to quickly think about what the E/C, H/C and E/S stand for and it jolts you out of the book for a second. (I literally read them as ECK, HIC and ESS lol and my brain was like ‘wut are you reading?!’)
But hey! This is your book so you do you babes I’m just rambling at this point.
Same deal for x Reader clothes- I don’t give the reader actual named clothes, I usually insert it with [outfit you would usually wear] or [cute clothes] something gender neutral that allows the person to pick and choose based on their personal tastes but I have seen people give options for clothing selection which I think is a cute idea. Bear in mind though, that you will always have someone who straight up says “I wouldn’t wear any of those outfits.” So … you know… can’t please everyone lol
Characters goals and desires
There must be two things to a character that make them good. They need a flaw and a goal.
I explanation to you. (English is amazing)
I’m going to explain with characters from an amazing anime called Boku No Hero Academia if you have not seen it GET. ON. THAT. STAT.
BNHA- Midoriya Izuku
Flaw- does not possess quirk
Flaw- given a massively overpowered quirk that ruins his body
Goal – control the damn quirk
Goal – become the number one hero
Flaw – egotistical, over confident, bully (BUT WE LOVE BOOM BOOM SPARKY)
Goal – well we want to hope he checks himself a bit buuuut maybe that won’t happen lol
Goal – number one hero
Think of your favorite character… they have a flaw right? Good. Now do they have a goal? You betcha. Bingo perfect story.
A lot of BNHA fanfic stories have the reader possessing a quirk that is stupidly OP. We need weakness!! Weakness makes the character lovable. (I’ve been guilty of OP-ing my reader too so don’t do as I do, do as I say :P)
Another thing to remember when writing is you can use characteristics of your characters to describe them so you don’t overuse their name.
Todoroki looked at her. He sighed as he watched her work. Todoroki had always been intrigued by the way she did things. He could never tell what it was that drew his attention but Todoroki was definitely curious.
To this- using descriptive points of what he looks like-
The duel haired boy looked at her (he has 2 colours in his hair) he sighed as he watched her work. The handsome boy (because he is) had always been intrigued by the way she did things. He could never tell what it was that drew his attention but those heterochromic eyes (he has 2 different coloured eyes) held definite curiosity about her, in them.
You can talk about the characters features (hair colour, eye colour, face shape? – if it’s a stand out feature- or gender (if known)) this heaps to expand the vocabulary of describing the character in sentences.