for the most part I think they love each other quite similarly with quality time, sharing food, and being extremely physically affectionate but

Kai- invites Soobin into his orbit
Soobin- feels special

Soobin- Let’s Kai get away with anything, laughs too hard at all his jokes, tells stories that about Kai that only Soobin thinks are funny/cute
Kai- feels special

I think Kai makes Soobin’s life more easy and enjoyable. Like Kai can do anything and Soobin finds him fun and cute. Even when they’re arguing Soobin seems like he’s having a great time. And I think Kai is aware of how much Soobin likes him, which helps with his insecurity and makes him feel good about himself that he’s making someone soooooo happy, especially someone like Soobin who he admires and loves. So I think this puts them in a lovely cycle of Kai making Soobin happy, Kai spending more time with Soobin, Soobin being happier. And what makes this great is their compatibilities and shared interests. It all works out nicely! What could hurt the cycle is Kai not feeling needed, which would be such good fic angst 🤩 sorry for rambling idk if this even answered your question???