@NotSoBeautifulDiseaster
Charlie: First of all I'm a sucker for Hanahaki disease so you instantly got me there. Anyways not too much to critique but to go into more research of trauma and anger issues along with depressing. It might help a bit to see out he reacts with his father and if you should alternate/add to his personality. Overall nothing really wrong with Charlie.
Kelly: I love her design a lot actually,very unique. But to me it seems weird how she is shy but at the same time very violent. I think you should make her anti-social or more of an ambivert rather than describing her as shy. I also think you could exaggerate her "evilness" a bit more than just being violent. Think yandere but minus the whole romance aspect, also sadistic if that works for what you have in mind for Kelly.
Dawn: Dawn is pretty good overall but by only question is how she stopped herself from suicide? What exactly happened then? Did someone come and change her life or maybe she had gone through it but survived? If you've seem Heathers then maybe it could be like he backlash of what Martha got when she tried to kill herself. No one cared and still made fun of her.
Emma: I think you should go a but more in depth to what a pampered child like Emma would act like, you could add more to her personality and also her relationship with Kelly when they were kids? Did either of them try to make an effort to make up with their difference or did Emma ever accept Kelly for how she looked? Did she ever stand up for Kelly but then her parents taught her to hate her sister? Little things like this can show relationship at its current status and what the characters may want internally.
Cleo: I really like her design, very cute and especially her hair! Anyways, since she is a side character the backstory doesn't need to be as detailed as the other characters but it doesn't make too much sense to have her being such an optimistic character when she had seen people being hurt like that? Unless it is a 'state of denial' thing that she forces herself into then I would look over that again.
Terry: I love Terry a lot and I really don't have any critiques for anything! Very interesting backstory.
Tori: Once again, not maybe critiques for Tori other than unless the plot demands it or he overcomes the dysmorphia over time, then keep that in his backstory. It feels like something that he should stay as a backstory unless it is important in anyway for him to get over it during the plot. If you do this, then look into articles or just flat out research of what people are like when they start to love themselves again, and if you want to take it 3 steps further make Tori turn to a religion or some community that helps in a non-obsessive way like how Terry does. A lot of people turn to religion (just as an example) to feel safe and loved. (Also edit note, for the family section you put Terry twice)
Aaron: Because he is abused and bullied, go into trauma and how that would effect his personality and more. As for his father I don't think he should be an alcoholic if Aaron is tying to impress and please him at times, some abusers may hurt you one minute then the next give you money or act affectionate towards you, its a cycle of abuse that is hard to get out of but I think is better than him being drunk. It could be occasionally but not all the time. Also why is he opposed to hurting women more than anyone else? It seems a little weird to include but if its very important then add why in his backstory.
Darrel: First I love the contrast of his design with such a dark color pallet and then those nice green eyes, very striking. Next he seems like the 'strong-silent' type a bit too much so maybe giving him a softer hobby or something unexpected to his character. His backstory does collide with Aaron's so same critiques for his dad. Overall a good character and nothing too big.
Elijah/Claire: Because he is the main villain you REALLY need to add more details to his backstory and relationships to his parents and sister. You need to have why he stuck to his ideals and never tried to fight back and whatever trauma he went through and exaggerate it (but not too much or he will seem whiny/bitchy). He is your main villain and even if he is just a 'pure evil' villain he still need to have motivations and end goals that seem right to him but wrong to everyone else. His backstory doesn't need to be so complex and complected but it is lacking and not strong enough to convince the reader/viewer that what he is doing is reasonable (to an extent or in his eyes) without him seem boring or too 'cut and paste". He isn't a bad character just he is lacking and needs more detail especially if he is the main villain. Very important. You may have noticed I didn't include Claire yet but that is because I want to know about their relationship. Their backstories do collide but not in an extreme enough way for them to be siblings, do more in depth to what they are like around each other and their parents too. I also think you can make her more of a yandere but may minus a bit of the murdering part but rather the obsessiveness and stalker-ish ways. Overall I'm not to worried about Claire since she is a minor character but for Elijah you NEED to elaborate on his backstory and motivations more.
I think your characters are really well thought out and have a lot of attention towards each but you need to go into the more technical stuff and if they were a real life person, how would act with seeming like they would overreact? I recommend you watch a YouTube channel called Overly Sarcastic Productions. They talk a lot about writing and certain tropes and characters (like villains) and how they are done and what is good examples and bad. I've found it helpful for my writing and hopefully you will, especially for Elijah. Go on to the channel and go into the playlist and click on the one that says "Trope Talks", very helpful information that I highly suggest,