just to see you in the lighting of the embers

Nakhun expects this relationship to simply work and to be because they're bonded soulmates and the rest of what makes a relationship will come from being exactly that so he doesn't reassure Phatsa and he doesn't understand the idea of them not being soulmates or having a type because he's always expected to have who he would love be picked for him so he never tried to get into a relationship or fall in love before this. Why would he?

But Phatsa has lived, up until this point, a very different and very innocent (in this specific regard) life. He's never considered the idea of a bond or of soulmates or of someone else picking his partner for him. He's on the path of a traditional love story and he's trying to rebuild that story into the soulmates bonded bite story he's found himself in. He's asking Nakhun to build their relationship without thinking about the bond because the bond, to Phatsa, isn't the relationship it's just a Thing That Happened.

The way that Nakhun is always super aware of the lack of consent in their bonding, and so is being incredibly careful in every other encounter. The blindfolding was more symbolic than anything, but it was an effective way to let Phatsa feel like he had control over the situation. It tells us a lot about Nakhun's level of care for Phatsa.

They also do a really good job of show-not-tell with the fact that Phatsa has started to accept not just his new reality, but that this reality consists of being the spouse to the eldest heir of a this high status family. And as such, he's taking steps to assert his authority in that domain. That's a level of commitment we hadn't seen from him yet, and it tells us a lot about where Phatsa is mentally.

Both characters are still very flawed - Nakhun is extremely stubborn about revealing weakness, and Phatsa is deeply sensitive about not innately being the kind of person Nakhun would have chosen without the bond, and we're definitely going to get more conflict around these things.

“The sound of your heart beats so loudly, it hurts my ears.”

"You have these lines you won't cross. But then you cross them. And suddenly you possess the very dangerous information that you can break the rule and the world won't instantly come to an end. You've taken a big, black, bold line and you've made it a little bit grey. And now every time you cross is again, it just gets greyer and greyer until one day you look around and you think, There was a line here once, I think."

Nobody suspects the cute boy

"I don't have any intention of being gentle with you today."

Taeseon's affections are becoming more subconscious