[Quick thought dump after recent interviews re: character relationships shown the manga bc I think I'm starting to get hang of Shirai's views]

Although characters are shown as trio/a group, the theme of duo partnership exists and it's pretty clear that as per Shirai's intention,

Emma's partner is Norman. Now this term "partner" is ambiguous and Shirai never used it for these two, but he used it to refer to Ray and Ayshe so let's borrow from there.
Ray doesn't exactly have an established 'partner' atm, the plotline with Ayshe remained unexplored

even now in spite of having her in series initial series setting (and once again, Shirai brought it up. It's the 4th time? Sensei really wants to write about Ayshe...)
When we'll get the Ayshe side story (which will also include her life in human world) it's likely that

there'll be interactions between her and Ray (maybe).
At the moment, the only similarities/contrast between them are their backgrounds (parent issues) and appearances.
Personally, I don't think when Shirai used the term "partner", it is exactly romantic but more like foils,

'two sides of the same coin'-thematically parallel characters that contrast each other. (But Shirai had been doing it with a girl and a boy.)
Now return to Norman and Emma. Although there are some contrasts between Ray and Emma, Ray (in Shirai's words)-essentially

Shirai sensei himself sees Emma and Norman as a 'set.' He likes the sun and moon analogies (although he hadn't come up with it by himself), sees them as reflections of people he yearns for (two dazzlingly kind people, one with high sympathy and other who is extremely reliable)

and now with the recent interview, sensei made it clear that "if Norman were a prince, the princess would be Emma", but that's not Shriai's intention. From author's perspective, their positions are a Knight and her horse. Sensei used Tezuka's "Princess Knight" characters

Sapphire and her horse Opal as an analogy (although Emma and Norman are not modeled from them. Shirai sensei takes a lot of references from Tezuka manga)

In children's stories, prince and princess rarely work together, there's a theme of protecting

the princess. But Shirai wanted to show "partnership"-that's why they can't become a hero and a heroine but rather a female focal character and a male supporting best friend who is her partner in her movements.

In Norman's absence, Ray continued playing that role

(Ray cooks, Emma hunts-reversing traditional roles) but Shirai didn't make Ray and Emma the thematic partners where they're on each other's opposite poles.

Instead, Ray's character centers around being a protective guardian for BOTH Norman and Emma, "he's the first

to see Emma and Norman's hidden intentions", "helps Emma and Norman to take a step forward" (according to his profile), while Norman and Emma are the ones who lead from the front with their different views and perceptions, so they're the opposites.

To Shirai, Ray is a character

carrying the essence of GF escape because his story was basically a complete work within that arc. Shirai eventually developed Ray. But,
his firm intention was letting Emma grow by herself and form her ideals alone. So, Ray's role and contribution were intentionally suppressed.

An important aspect of Norman and Emma's portrayal is their genders. If Emma were a boy, it'd be flipped and Norman would be the girl (reference: fanbook), it was shown like that even with their respective ancestors.

To Shirai, it's important that Emma is a girl. He had

10 reasons why he chose a female protagonist. Even if Emma is more like a young boy, she must have the features of a girl and not be a tomboy. (according to her character setting) Some of these reasons are her empathy, being 'mom's daughter' and her rival.

Contrasting that, it's also important to Shirai that Norman is a boy. Shirai sensei summarized Norman's arc in the artbook as "showing his weak and uncool sides to Emma", and in fanbook, his concept was written as a boy whose

mindset is most similar to the old stories where boys carry certain responsibilities on their backs and Norman had the mindset where he "must not show his weakness/always be cool in front of a girl". (The girl is Emma.)

So, while Emma was a girl freeing herself from her gender role, Norman was trapped within his. Shirai wrote a story of revolution, so Norman had to free himself. The final chapter shows the culmination of Norman's growth as a character.

Something most people are interested in is

how much the romantic potential played a role while writing the partners. I'd say, Shirai is fully aware, but he wants to keep it suppressed.

He was jokingly jealous of Ray getting a beautiful girl like Ayshe (he's 100% joking there bc Ray is Shirai's fictional buddy, kind of)

In WSJ issue 14 interview (screencap below), Shirai said "Norman's feeling is different from [only] romantically loving a girl", and in response to Sugita in fanbook, he said "it's best to pick up both [love] and [respect]" to perceive his feeling for Emma.", both statements

confirm that Norman's feeling includes romantic love (although it's different in Posuka's perception, it has to be kept in mind that the characters are Shirai's and not hers).

I think it's an extended essence to the roles of a man and a woman established in society,

how Shirai wants to reform these roles; and it also highlights Norman's self-awareness of being a boy. Norman's romantic love for Emma is subtly present and it's essential, but romance not the main focus of TPN.

Although Shirai always approaches their relationship from

Norman's point of view, it's not like Norman has a unidirectional unreciprocated admiration and love for Emma. Rather, Norman and Emma are partners where both care for each other very dearly. Their relationship isn't about love/unrequited love but a

mutual bond of respect and partnership between a boy and girl to save the family together, fill each other's lackings in ways they expertise in (Emma with her 'feminine' empathy with underlined physical strength-which is usually shown in boys in a fiction, Norman with

the 'masculine' brute force and combat with underlined frail and weak physical constitution-which is usually shown in girls in a fiction)

So imo, TPN isn't about ships but relationships, "platonic" (as Posuka sees them) but also "male and female partners" like the parents in

a usual family. Shirai doesn't want to focus on the romantic side of it but the camaraderie, where they work through their hardships to reach the same goal.