Dess Knight is probably the most popular theory for the Knight's identity, but personally, it doesn't sit right with me. Above all else, Dess's number one character trait is that she is the lost girl. That's where everyone's trauma or issues come from. But if Dess is the Knight, and people know the identity of the Knight (which Kris obviously does, given they prevent us from removing their helmet), then she's not lost.
To go through with the idea that she is both the lost girl and the Knight would require that Carol's and Kris's motivations be reevaluated, since they're not trying to find Dess. Then maybe they're trying to fix Dess? But then what is the condition of Dess? Is she like Flowey? Then that means characters need to have realized the knight was Dess, have figured out a plan to put her back to normal (unless they're okay with leaving Dess as the Knight, which is a separate can of worms), and convince the Knight to work with them, these facts of which I feel have not been foreshadowed in the story thus far.
I won't deny that that the Knight has associations with Dess, but Dess's thing is that she's not around. And associations don't have to mean it's exactly Dess, especially given how it conflicts with her core character trait of being lost.
Of course, there's always the idea that "Toby will reveal new information putting everything in it's place", an idea that I readily accept, but given the information we have at this time, Dess Knight kinda ignores the fact Dess's entire thing is that she's missing. Maybe Toby will reveal that Dess is the Knight while also being lost, and that Kris and Carol know this, and they were given a plan by Gaster or someone on how to fix her, but Dess Knight really feels like it puts all the information that actually puts Dess in a position to become the Knight in the information that is yet to be revealed.
Personally, I feel more inclined to believe Rudy Knight, though my biggest reason as to why is because I don't think Dess is the Knight. A few clarifications about Rudy's condition: it is yet to be determined by Doctors, there's been no mention of it being terminal, and it's implied to have been around for only a few days. If Dess isn't the Knight, then it's almost certainly another Holiday. Though, I won't go much more into it since this isn't really supposed to be a Rudy Knight post, and because it has it's own issues (though the issues bother me less than Dess Knight does).
There's also the matter of UNUSED, and how, given the information that has been most strongly connected to Dess, is probably Dess herself. Is Dess both self-aware of their status in the code and running around as the Knight? There's also the fact that Kris stops the player from seeing the Knight's face. If it were Dess, a character we've never seen, why bother obscuring it? If she only exists as the Knight, then it doesn't matter what her face is. If it's someone else who is playing it cool, or whatever, and goes uncover as the Knight, then it just doesn't make sense for Dess to be the Knight.
But let me know what you guys think. Do you think it's more likely for Dess to be lost, the Knight, or both? If you think it's both, what are some of your theories (REAL theories, not just a few scattered points) as to her condition, and why Kris and Carol might be working with her? I'd like to hear what other people have to say on the matter.
