Kris Deltarune is canonically plural
Thanks to ppl informing me that possession does infact count making my claim valid >:p but now it's time to infodump.
At the beginning of deltarune, there's a mysterious voice that guides you on the character creation process. However after creating a whole character the voice denies you the right to play as said character, informing you that you have 0 choice on the matter leaving you to be forced to play as Kris. Who prior to the events of chapter 1 has always been their own person.
They had a verity of interest, and activities they partook in with the major one being playing the piano. Prior to the game its said Kris played the piano frequently at the local hospital despite the piano having missing keys. The hospital receptionist also comments that they play beautifully, you are able to play this same piano but unfortunately when you attempt to play this very same piano whilst in control of Kris's body the piano sounds horrible. Indicating that you do not have the skills that kris does despite being in the very same body. Also when you attempt to play the piano infront of Susie it still sounds bad, and Susie comments on them looking upset.
This isn't the only indication that Kris is a being seperate from the player.
Other moments/events include:
-any time you make a choice kris doesn't like/agree with being it dialog or just actions its shown to be strained and forced on kris's end.
-They protect Susie from being attacked by the card king despite the player/you not doing anything.
-They don't allow the player to fully inspect anything related to their home life. Closing their eyes when you attempt to look into Asriel's room, and closing a book when you try reading why Toriel and Asgore divorced.
-in chapter 2 when you're drinking the tea flabour of your party mates (Susie, Ralsei, and Noelle) its shown that ralsei's tea does a lot less healing for Kris whereas Susie's tea heals the most for kris, showing that ralsei is more the players friend than he is Kris's friend. (They're still friends but it's shows that Kris happens to like Susie a lot more.)
-during chapter 2 some/a lot of the time when Ralsei speaks its not directed towards Kris and is directed towards YOU. As if he knows the difference between you and Kris but he doesn't mention it directly.
-during chapter 2's snowgrave route while Noelle seems to be talking to Kris and 'following Kris's orders' its actually really out of character for them. Kris would never do that, and the voice coming out of Kris doesn't sound like theirs. Once again showing that it is you who is in control of their body and their actions, and you are directly commanding their friend to kill others(and their friend berdly)
-chapter 1. When you first meet sans there's an option to tell sans "nice to see you again." (Paraphrased), which is strange considering Kris has never met sans, and yet you are able to speak like you know eachother? Let alone asking about papyrus which is weirder considering once gain Kris has NEVER met sans and therefor never met papyrus. How does Kris know papyrus? It's because it's once again you the player who is the one doing the speaking.
However the biggest evidence to Kris's plurality is everytime they rip our their soul. The first time they do it is in chapter 1. Locking the their soul aka the soul that YOU control away in order to steal some food during the night. And the 2nd is in chapter 2 with Kris once again ripping out their soul in order to slash his mother's car tires and create a dark fountain setting stage for chapter 3. Kris is fully taking front in these moments and you are locked away unable to do anything to stop them.
Although you, the player are in control most of the game and make the most decisions Kris is still their own person. It's kinda like a puppet on a set of strings fighting to gain back their freedom.
This also works with deltsrune's current known secrets boss's jevil and spamton. With jevil going insane after speaking to a mysterious person locked away in a cell but believing that he's the one whose free and everyone else is locked away. And spamton being a salesman + puppet who lost all his fame and fortune after losing contact with thst same mysterious person. (And spamtons boss fight is him litteraly being held up on strings)
Or I could just be looking too into it.
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