I honestly thought they're gonna switch too. From what we've seen so far, Wonseo seems to lead their intimate moments. My guess is it's her need to be in control. Living with a mother like hers and being instructed by the sunbae for most of her life, being with Eunha seems to be the only time she could be free thus she has the need to be in control as self-defence mechanism. Hell, her tendency to make rash decisions is exactly her need to be in control.

Aw man, I really thought they’d finally switch… but nope. Also, I don’t even know how to feel about the recent chapters. It feels like the story isn’t going anywhere, and everything’s just a mess. Can they just switch already, for the love of God?