I really love the dynamic between Yoohyun and Yerim. Since they are the opposite of one another, not only in attributes, but also personality. Like how Yoohyun doesn't really have any real desire for anything other than to be with his hyung and is more than happy to just stay as he is so long as he is by Yoojin's side, Yerim on the other hand desires recognition, and wants to be the best, and someday she'll fly away from her nest.
Their contrasting personality highlights how the Perfect Nurturer title fits Yoojin, as he accommodates both of them, in Yoohyun's case, allowing him to stay as he is without being pushy over wanting him to be something else, and with Yerim, allowing her to grow and letting her go to explore the world without clinging to her and demanding her to stay by his side.
Suddenly reminded of that one reddit post criticizing Yerim and her personality (the one that's like, they're reading msch because they want to see hot men, and Yerim would be better as a boy since Yoojin would find her more relatable(?) that way). Ignoring the blatant misogyny, if Yoojin could only be nurturing to those he finds relatable, then the title perfect nurturer should be stripped off of him because are you really deserving of that title if you could only be nurturing to those who are 'relatable' to you?