i know a few people have mentioned it before already but i want to say that the more fitting parallels, in all honesty, are racism and classism. (bare with me here, this is a long post and i am very very ill.)
regardless of which route you take, the one outlier in deltarune's story has always been susie. every time, susie is the one that throws a wrench into the narrative's plans. she's the 'violet tormentor', she's the dragon, she's 'the girl with hope crossed on her heart', she's the one who is currently set up by the narrative to break the prophecy. literally. she has seen the prophecy and broken the damn panels to it in ch4. she is what makes the entire normal route possible, because she has hope crossed on her heart.
one of the big themes of deltarune is about destiny and building it for yourself. over and over again we are told that A) the prophecy sucks and B) that it is inevitable. ralsei firmly believes it will come true, susie firmly believes it won't (because she's going to stop it), and kris... is kris. they're working with the knight & co, presumably to uphold the prophecy and presumably in order to save dess, but it's too early to say -- that's neither here nor there.
the normal route of deltarune is literally about the heroes' journey in trying to break the prophecy. by contrast, weird route seems to be upholding the prophecy. we don't know what that prophecy is yet, we don't have all the details, but that's where things seem to be headed.
the weird route aims to gain control over every aspect of the narrative. it's associated with a lack of control, a lack of agency, wherein the characters give in to commands regardless of whether they desire to do it or not in order to 'proceed'. it aims to control the characters like puppets -- something susie is staunchly against.
there are discussions about whether or not susie is the third hero mentioned in the prophecy for a reason. if the weird route does uphold the prophecy as implied--and in turn, goes against the theme of building your own destiny by having the prophecy become true--then noelle's presence in the weird route only further affirms susie's place in the normal route. noelle being pushed by the narrative to become under our control, her themes of submission (and either complying with that expected submission in the weird route, or subverting it in the normal route) -- all of that is intentional. because the weird route is an exercise in the player's will and control.
susie's character arc revolves heavily around her being outcast from society. from day 1, we are introduced to her as an outlier. she's the new girl, she's a bully, she has no friends, she's a trouble child. no one in hometown likes her. the adults tell the kids to stay away from her. appearance wise she has dark hair and purple skin, she's tall and menacing and scary and strong and "violent".
susie is heavily poc-coded, specifically black-coded, among other things -- namely, she is heavily implied to be from a lower economic background or class, arguably even moreso than her racial coding. (she also could be read as immigrant, adopted, trans or fat even -- the list goes on. all of those are groups which you could read susie as belonging to and/or representing, but the important ones here are poc and poor as they are the ones with the most evidence to support them.)
of course, i don't say that because i think black people or poor people are any of those things -- but that is exactly the point. those are traits commonly associated with those groups due to the racist and classist society we live within, hence why coding exists in the first place. susie is objectively incredible, funny, determined, realistic and optimistic, and a beacon of hope. and narratively, she is contrasted as being everything that noelle isn't.
by contrast, noelle is the perfect poster child of white american suburbia. she's smart, she's kind and friendly and sweet. she dresses effeminately, susie doesn't. she has little buck teeth, susie has pointed teeth. she has pigtails and susie's hair is in her eyes. noelle is innocent, childish, girly; susie is big and mean and scary.
i won't say noelle is white-coded, that is a bit blurrier, but all of the pieces are there. namely, she's fucking blonde. her mom is blonde and light-skinned. her family is highly religious and upper-middle-class, if not just upper-class, and they live in a goddamn mansion. those are all traits associated with the majority class, traits which are seen by our society as desirable.
we have every reason to believe monster-classism exists. noelle is the childhood best friend, the girl-next-door, the 'kind white girl'. susie is the bully, the villain. social norms of both deltarune's universe and ours imply that noelle is the preferred romantic candidate for kris, not susie. and it's NOT because of their gender. the weird route is allegorical for racism because the player prefers to mold the Submissive Innocent White Girl to their whims in order to play god.
metatextually, we come to expect rpgs to pair off the MMC and FMC, and most people would agree that noelle is our stand-in for the FMC. everyone is getting hung up on the gender aspect of things instead of the race aspect, when the race aspect is infinitely more important than the gender aspect. there's this trope in fiction, where white FMCs are allowed to date the MMC, but black FMCs can only ever be the best friend at best or the villain at worst -- it is a widely known phenomenon. of course deltarune is aware of it and subverts it in the normal route.
on the flip side, the weird route is implying the inverse: that noelle and kris are the most romantically compatible due to being seen as the most 'desirable' candidates. mind you, kris is not just our MC but also from a similar economic background to noelle -- and a similar racial background, if you take noelle's racial coding into consideration. it's not a stretch to say that, while kris is aracial, they are not coded in any one direction and our society expects 'white' as the default option; ergo, they are expected by the player to be white because we have come to expect white as the default, regardless of whether they are or are not. unlike their gender, their race IS ambiguous, and that is part of the point!
look, to be clear: i am not a good person to be discussing race in fiction. i'm white. i won't sugarcoat it, i don't know jack shit about the lived experiences of black people because i have not lived it. so far, i have been using my experience as a white person in white suburban american along with the knowledge i have acquired from listening to black people in order to connect the subtext that deltarune is trying to convey. i might be wrong about some things. but if there's one thing i can speak on, i am nonbinary, and i know enough to be able to say when people are being transphobic. i can say very clearly that it is transphobic to push the "heteronormativity" reading onto kris.
gender is absolutely a theme in deltarune, but it's the wrong conclusion to come to with the weird route. both susie and noelle are girls. as mentioned above: kris is, and will continue to be regardless of player input, nonbinary. neither one of them are straight for dating, or not dating, kris -- nor are they any more queer for dating/not dating each other. ALL THREE are explicitly, unabashedly queer. it is not 'lesbian erasure' for kris and noelle to date, and quite honestly if that is your takeaway from the weird route, you must be playing this game with your monitor turned off.
i understand why someone would make the mistake of reading the weird route as 'representing heteronormativity'. but the thing that i've tried to hammer home is that the heteronormative reading is transphobic because it is A) not supported by the game's own narrative, and B) only works if you enjoy misinterpreting what you're reading. yes, i understand where it comes from, but again, it only works if you explicitly disregard kris' identity. you would have to actively ignore everything the game itself is telling you and only view it within the context of OUR society.
monster society is not heteronormative. no one in deltarune misgenders kris or equates them as being male. hell, it's not even clear if humans have a social concept of gender in UTDR. that is an interpretation only given to them by the people playing them -- one that, ironically, contributes to the very same problem it points out.
i was going to go on (another) rant about player input and how much say we have over kris especially wrt the weird route, but that's just it: we have control over what they do, not who they are. i know i've said it already, but you cannot remove kris' gender from them no matter what route you play. you cannot force that on them, it is not physically possible. they are nonbinary. they will stay nonbinary no matter what. there is nothing "heteronormative" about that.
you can 'force' kris to give noelle the ring. you cannot force kris to be a boy, or male, or masculine, or to perform a masculine role. that is a reading YOU, as the player, have given them. and if you read them that way, YOU are transphobic.
on another note i don't know enough about spamton to speak to his character (i've never cared for him, sorry.) i know people love bringing him up in discussions about the weird route because he plays a part in it but again, i don't care because i don't have a phd in spamtonology. so if someone else wants to do that, go for it, but i think this stands on its own pretty solidly. that's all the thoughts i have on the subject.