Hot take: There aren't other interpretations of the scene, there are only willful misinterpretation.
This interaction is clearly not meant to be mocking. Sure, Flowery is talking down at Ralsei but not in a way that I think can be truly read as malicious. Also, Ralsei isn't the kind of person who would take offense to be called a princess, so why would it be used as an insult here. (Heck, in this game, it being used as an insult doesn't fit how the world and characters seem to interact with gender. But I could even be wrong about that that doesn't matter.)
Flowery is a character meant to get under Ralsei's skin, so there's no reason to have him use an insult that wouldn't be effective on the character as we know them.
Unless, it's meant to reveal new information, and I doubt the story wants to reveal that Ralsei is secretly a misogynist so... what else would it be telling the audience about this character? a character who is defined by the prophecy as a prince and the shapes everything they do are and allow themselves to be around that? Hmmm...
Why call that character princess like it's a big drop moment? In a game with a non-binary main character and several lesbians? In the chapter where a canonical trans woman is the secret boss. Secret bosses, which usually parallel one of the core trio. Who's the only one of the core trio who hasn't gotten a boss that parallels then yet? The same character who has the most interaction and friction with the character closest to that boss over the course of the chapter.
But I'm getting off track again.
Why would you call that character a princess? Well if you were some sort of flower-man doing it during a scene where you are talking about how much they should allow themselves to be happy, be themselves without worrying about others and try living for themselves rather than following the prophecies rules then you might say it if you wanted to make sure that character knows, you know exactly who they are.
If you were a Game Dev, you might say it to make sure the members of the audience who haven't picked up on all the little hint you've been sprinkling around the game, such as the pink white and blue "princess ribbon" (Ribbons that the game often encourages you to put on a certain prince)
Among other interactions and thematic parallels.
The point is there's no way that this Frame is just a throwaway line, there's too much focus on it, too long of a pause too important of a moment.
And that's not even getting into the drink color, I know it is the color of Kris's dark world outfit but here is the thing, things can have multiple meanings and one meaning doesn't invalidate the other. If it were the only evidence then I would dismiss it too, but in conjunction with the line and just everything else every video on the topic of Ralsei's gender will point out.
At a certain point, it just becomes Occam's razor.
And somehow we've returned to the days of years past, gazing back afixed a past we forgot to see those we called fools were seers in disguise as we look with new eyes.
And ourselves see that...
Ralsei is a girl.
I'm so sorry, tricycle, or whatever your channel name was.
My first impression from all this information was the opposite, that Ralsei was a trans guy. Flowery is kind of the twink Ralsei wants to be, charming and suave, which is why he's infuriating, and the secret boss is a projection of his princess alter ego. Flowery calling him "Princess" to me read as teasing by misgendering and also outing him to his friends as a trans guy. He's doing the destiny fate thing as required but being a prince instead of a princess to not stray too far from the rules he holds so dear, because he's a lil soft boi, even when he just wants to go ape shit instead.
I could also see him being transfem though, and Flowery teasing him by outing him to his friends in similar fashion. It would track better with Flowery being essentially "Nice" even if he comes across as mocking to Ralsei, who doesn't want to be outed and/or misgendered and doesn't want this dark-world-adventure-journey to morph into one about his journey of self discovery. He's too shy and not ready for that. He never wanted to be the princess on center stage, whether because he's transmasc anti-princess prince or because he's a shy transfem who isn't ready to wear a dress and be the princess in a dramatic unveil and doesn't want to encourage that kind of adventure to "grow" from this dark world.
I didn't necessarily buy that Flowery is fully "Nice" especially if he's overtly outing Ralsei to his friends here. Maybe that's part of the point though. He's either like "I do what I want and you could bloom and be yourself for once here, Ralsei. Let's do it!" Or he's like "Come on, you're really just a girl aren't you? I'll out you to your friends and either emotionally devastate you so you can't fight me, or you'll discover that your friends support you no matter what and maybe you'll be a little more comfortable with yourself. Win-win." The first fits more with the "nice" projection of Flowery and the second is slightly more sinister and malicious but also kind in a tough love kind of way.
I love the tension of that though, and the fact that we don't need to know the exact details of Ralsei's gender journey (he's shy, okay) in order to get the way Flowery is picking on him for his shyness and resistance to being the center of the narrative arc as well as his gender weirdness he definitely has going on somehow. I also love that the tension allows for so much head-cannon and debate and everyone who's ever been a little shy and not wanting to be the center of attention while figuring out their gender can relate.
And to those wishing to Raise Occam’s Razor, after this line of dialogue… all ingame text starts referring to Ralsei as “they/them.” Both diageticlally— in dialogue, but also the game’s UI. It doesn’t get more “simplest answer” than that — Ralsei’s tenuous connection to either gender, and the freeness with which they switch between gendered presentations (and horse? lol) and the they/them pronouns suggest they’re neither boy nor girl.
Bonus: Ralsei appears to have, a tenuous relationship with physical form. Ralsei can turn into a horse. When ralsei is injured, there is No Body Left. Which does suggest a degree of, for example, fluidity. When ralsei is injured and there’s no body left… ralsei is JUST CLOTHES. So I imagine there’s going to be a very interesting relationships with the things that are fixed in a way you are not.
It may well be that Ralsei is a girl or has in fact has already transitioned and chosen to be a boy who still enjoys trappings of feminity, and that’s how it ends up! And if/when that is the case, I will be delighted! But I do think it’s very uncharitable and unkind to other queerfolk (especially to not binary people, who have been disregarded fully from the conversation) to say that there is “only one interpretation.” We do not know yet for sure, and there’s strong evidence to point to more than just a single possibility.
I think this supports my "Ralsei is a tree" hypothesis as well.
I actually love the liminality of Ralsei's gender so I think foreclosing on possibilities nowkinda spoils something in the narrative for me. It takes away Ralsei's own choice and agency to decide what gender they must be. It skips past Ralsei's journey to make a nice satisfying end instead of sitting in the point of tension this period represents.
I’d be happy if Ralsei were a tree. Or all the trees. One giant root system beneath hometown.
