it is very obvious that kitty needs a deep emotional bond to fall in love - its why she is very in love with dae when she first comes to KISS in season 1. dae lying to her makes them grow apart, because she can't trust him as much as she's used to, so she can't come to him with her problems. in addition, kitty needs her partner to be open and honest with her, but he doesn't give her that chance by not telling her about the fake relationship until it's too late. that is a large reason why they don't work anymore, and why she's already moved on mentally.

then you have yuri - kitty develops feelings for her as their emotional bond grows (they discover their mom's friendship, she helps with juliana, etc) . it's clear that she's still not over her when they get back. however, kitty does start to move on after yuri stops talking to her as they're fighting. i believe a key moment in this process is when kitty is trying to tell her something about her parents in the storage closet, and yuri just brushes her off. there's definitely some distance after that moment, which is cemented in ep 6, where kitty kind of confirms how much that hurt her and stops having k-drama moments with her.

this character analysis is not meant to throw either dae or yuri under the bus. they're both teenagers, dealing with a lot of outside issues that influence the way they act. dae couldn't be open with kitty in the way that she needed, and yuri is definitely self-centered (which she acknowledges, and tries to work on). kitty fell for both of them because they had that emotional connection, but when that connection falls apart, so do her romantic feelings.

the reason minho is the best partner for her (at the moment, at least) is that he's open with her, while also being consistently there for her (like in the hot tub scene). she doesn't see him as an option (even in the heist scene, he's not her first choice) until after her feelings for yuri have kind of gone away. then, she can see that minho gives her balance - unlike how dae never came to her, minho asks for her help with his fight with dae, showing that he can be open with her. unlike yuri, he helps her with her family stuff even when they were fighting, prioritizing kitty over residual anger he might have because he knows how much this means to her.

relationships are a give and take, and kitty needs that to form the emotional connection she needs to fall in love. over season 2, minho grows into the perfect person for her for all the reasons mentioned above. i hope season 3 will cement that relationship, because there was honestly so much development for these two and i love them so much.