The wiki lists the Knight’s pronouns ars they/them and it/its. However the only instance I can find of someone referring to the Knight with they/them is Susie in Chapter 2, shortly after having learned of the Knight’s existence. All the Darkners who seem to have been acquainted with the Knight use “it” and all in-game text either also uses “it” (The enemy suddenly let down its guard!) or avoids pronouns completely (The image changes... the helmet begins to come off.). It’s possible that Susie simply used they/them pronouns for the Knight because she didn’t know who it is and didn’t assume a gendered pronoun - since the name Knight implies a person, it would’ve felt more natural for her to use “they” rather than “it”.
Is there any instance of someone in the game referring to the Knight as “they”, other than Susie in that one scene?
That’s not really related to my question. People can use multiple pronouns, but the issue is if the Knight actually does. It seems to me that everyone who has some idea who/what the Knight actually is refers to it as “it” exclusively.
Ah, I see. As far as I can tell, Susie uses they/them all throughout Chapter 4:
* Maybe... Maybe that's why the Knight captured Undyne?
* They wanted to take their code so they could get in...
* If the Knight's only goal was to hurt people...
* They would have acted sooner, right?
* That goddamn Knight...
* Making one right where everyone can see...
* Kris. Let's think logically, right...
* There's no way... they can get out of there...
I don't think anyone except Susie does it though.
Edit: Wait a minute. The second one is said by Ralsei, not Susie.