Honestly speaking yoonji at first couldn't have cared less about the girls in this other group, they were just a means for her to debut and show everyone that looked down on her that she could make it on her own, proving that her choices in life weren't just a way of rebellion but her way of life. But the more that they spent together and got used to one another the more that she slowly started to care for them and would now do anything for them, even though she would rather die than tell them that to their faces.

as the oldest she feels a sense of responsibility for the girls, and will always happily take all of the criticism if it means that the others, especially the youngest ones don't have to have that burden and can just do their best. She takes care of them in the background and although she's not the best to be there for them emotionally she is there ready to protect them from the cruel industry and anything else that might end up in their way, because it's the least that she can for the group that had accepted her as she was, and she will never take that for granted.

Yoonji owes minho a lot, especially since he had still vouched for her after her refusal when he first asked her about being in the new girl group. he hadn't given up and somehow convinced her, to this day she'll still say he tricked her into it, and she's forever grateful to him for the chance and opporunity since no one else would and always ended up giving up on her. She does try not to cause too much trouble for him with and confrontational nature, though a lot of the time she just can't help herself and has a really hard time controlling . they don't have a bad relationship and honestly there are only a handful of people who she will listen to at any point in time and minho is on that list. 

Yoonji is probably the closest to misaki in the group, and a lot of it probably has to do with the fact that misaki won't put up with her nonsense, but they have a lot of the same thoughts and aspirations for the group, though yoonji is just less likely to say them out loud. she acknowledges her as the leader of the team, actually feeling a bit guilty about it since she's technically the oldest in the team, but it's misaki who has the burden of leading and taking care of this team instead, since there is no way that yoonji would do even half a good a job as misaki. they do heads a lot since both are stubborn and very set in their ways but they tend to get over it quickly. yoonji is a huge advocate for misaki and anyone who questions her leadership will have to answer to her personally. Also they both work on composing songs and yoonji really values her opinions so that she can improve her own works. 

Yoonji is actually quite awkward around haena, mostlyf becasue she's worried about unknowingly taking advantage of her. not to mention haena is very non confrontational and quiet, the complete opposit of yoonji and any means of making conversation ends up in an awkward mess for the both of them and those around them. however she does admire the girl's hardwork and doesn't deny the girl's skills. she doesn't try to argue too much when faults are pointed out since she knows that haena means well and only wants the team to be the best they can be. she's also an advocate for haena's skill and is there whenever anyone else tries to bring the girl down. 

Yoonji is super akward around yoonhee, for a lot of the same reasoning as haena, except yoonhee is worse. she feels like at any moment the girl is going to burst into tears and well yoonji isn't the girl to go to when you need a shoulder to cry on. he has to literally walk around on eggshells when the other girl is around, which then only ends up in disaster. it's not that she hates the other girl but there's a lot going on and yoonji is not equipped to handle the emotions that yoonhee shows, although she does try her best to be there for her in other ways. 

yoonji has a pretty decent relationship with jieun mostly because it's hard not to like her friendly nature, and well it's good that someone in the group can mediate since obviously she can't do it herself. Her dramatic nature will make yoonji roll her eyes and possibly say something depending on how dramatic she makes it out to be, and the rebellousness might end up rubbing yoonji the wrong way sometimes, but she tends to get away with it since yoonji has a bit of a soft spot when it comes to the younger girls.

Yoonji has a huge soft spot for Sejin, and feels like she has to constantly watch over the girl because she's naive. she does get fed up with her childishness but it doesn't take much for sejin to get back on yoonji's good side. The girl is just too cute for her not to want to shower her with subtle affection. Honestly all sejin has to do is show interest in anything, for example a plushie, and yoonji would end up buying it for her and leave it where the other girl can easily find it, but not say anything about getting it since it's not yoonji's style, and she would end up feeling awkward about the attention. she's often seen taking care of sejin, whether it's fixing her hair and clothes, or just making sure the girl doesn't run into anything.  

Kyungmi is another one who yoonji dotes on a lot but unlike sejin she will tell the youngest to get her act together when she throws a fit and remind her of her place. But again it's not hard for kyungmi to worm her way back into yoonji's good graces, mostly because yoonji worries the most about the youngest girl and the very stressful situation they are in. Kyungmi also reminds her a lot of her own sister so she's extra particular to taking care of their baby. It's a lot of the same with sejin, making sure that she gets enough to eat and that she doesn't end up stressing herself out and getting sick because of it.