Okay, So, I have this character, his name is Ciel. Ciel is a nervous 14 y/o trans boy who was conditioned to always act cheerful and full of energy, to act with the eccentrics of a circus performer(which he was)
Now here's the thing, he's my main character's best friend, but also has a plotline of his own. The main character is a toxic person w/ a hero complex and narrates the story(they are very unreliable and try and make Ciel seem like the toxic one)
The main character(13y/o girl) twists things to make themself seem better, how can I show that Ciel is morally grey while still having the unreliable MC villianize him?
How to write an Unreliable Narrator
Hi! Thank you for your question. What you describe is a great example for an unreliable narrator. Here are a few thought on how to create such a narrative voice:
The big thing for most stories told by an unreliable narrator is having the reader at first side with them before the relevation of their true nature. This creates the big conflict the reader is confronted by. It's not about straight up lying to the reader, it's about exploiting their natural willingness to side with the main character, since they are closest to their thoughts, reasonings and emotions. While the voice of the narrator leads them down the wrong path, foreshadowing the truth behind their narrative is essential. It's like placing clues for a mystery, so the reader can look back on the text and realize all the ways they have been led astray, while the truth was there the whole time. So think about this story as a mystery story with the crime to uncover being the obscuring of truth.
Like in any crime story, the criminal needs a motive. "Being toxic" can be a character trait but in itself it doesn't add up to a motivation. If their motivation is to paint themselves as a hero, it might be crucial to explore their personality and their backstory for how this desire was produced and what their ultimate goal is.
One great example is the novel Gone Girl (spoilers, obviously): We learn about Amys story through her diary entries that paint her husband as violent, before the twist of the story reveals that she manufactured the diary to frame her husband for murder.
Another famous example is the novel Lolita, in which the narrator Humbert Humbert obviously twists the events of the novel in a way that paints him as the "victim" of the "seduction" of the 12 year old Dolores, to justify the sexual abuse he imparted upon her. The point of the novel is for the reader to be horrified and disgusted by his thoughts and reasonings, while being captivated by the hauntingly beautiful prose.
The next famous example would be The Tell-Tale heart. The fragmented prose of the text illustrates the narrators madness to the reader, thus marking him as unreliable.
Some ways to foreshadow the unreliable narrator
It can be quite tricky to place to clues that point to the narrator being unreliable. Here are some ways that can help with that:
a) Using other characters/POVs as a sounding board: A story using multiple POVs might be the easiest way to show the different narrators various reliability. The characters filter the events through their specific lenses and thus give the reader a way to piece together the truth.
b) Using the narration itself to instill doubt: this can be used by planting contradictions, by showing in real time the thought-process of the character twisting the truth, by establishing intentional "plot holes" that are later revealed to be part of the twist, by framgenting the narration in a way that indicated the narrators instability or by having the narrator justify events/acts/thoughts that are obviously twisted. Things can start out seeming very truthfull and reliable and then proceed to unravel as the narrator struggles to keep up appearances.
I hope this helped a bit.