frisk is tma because even though they can play through the entire game showing nothing but kindness and love to others, they still get attacked on sight by random monsters. every encounter with a new monster is a de-escalation process to show they aren't a threat.
chara is tma because of their hatred with their humanity, and passive suicidality. they're so disgusted and bitter towards mankind that they are willing to kill themselves in order for monsterkind to take its revenge. no reason is given, but it's possible that humans were abusive towards them or treated them poorly in the past. and this has hurt them so much that even after running away, even after finding a new family who loves them, they still feel so much hatred for humanity and for themselves that they carry out their plan
kris is tma because of everything hinted at in their past. they're a human adopted into a monster family. for the longest time they didn't know they were human, and wore fake horns to try and look like their family. despite being clearly and explicitly referred to as "they/them" in the text over and over again, they're still treated as masculine and sometimes even called "he" by the fandom at large. this masculinization extends to the game as well, with the "deodorant for men" and "mancountry: (non men are welcome too)". also the entire narrative of the game is about the disconnect between kris the character, and the soul controlling them. about freedom, and breaking out of the rigid structure of reality.
Susie is tma because she's stereotyped as overly aggressive and masculine due to her appearance. people assume she's a bad person based on nothing but vibes, a highly racialized and transmisogynized act that mirrors what so many "troubled teens" experience. Susie acts bad not because she is bad, but because people have just assumed she's a bully so much that she gives in and simply acts how people expect her to. it isn't until she hangs out with kris and lancer and ralsei where she's given the tiniest bit of unconditional kindness and empathy, that she is finally able to grow into a kind hearted and hopeful character and break free of the stereotypes people impose on her.
Noelle is tma because the snowgrave / weird route is defined by abuse and control, a metaphor for an abusive relationship that trans women often go through, as we assume the only connections we deserve are the ones that hurts us. she hurts and kills people not because she has any intention to, but she's being forced by kris (who is actually being forced by the player). her narrative is defined by abuse and control by parental figures: queen who acts loving and caring but is really just trying to manipulate her and use her for her plan, and her mother who acts cold and distant and implied to be abusive when she sends her to the kitchen after the encounter in chapter 4. also her room is trans flag colored.
ralsei is tma because their entire identity is a tool that exists only as means to an end. their only purpose is to help lightners, who by the laws of the prophecy are intrinsically "above" them. they have incredibly low self worth, constantly belittle their own struggles, and imply that they aren't real. they even offer themselves to be literally used as a stepping stool for others. despite the friendships and connections they have with others, they still cant see themselves worthy of love, or deserving of any personality besides what the prophecy demands. lost girl plays during a hidden scene which shows how lonely and empty they truly feel, that they assume they're nothing more than an object created for a specific purpose. one of the light world objects that they probably are (besides the green crayon or asriels fur) is a doll (the ralsei plush doll). in the few moments of vulnerability and actually personality we see, they are shown to like bows, cooking, and express liking their (very feminine) face and outfit and want to try and become more "ralsei-like"
berdly is tma because i think it would be really funny if she took estrogen