That is true, but I think that is why Su-ah is apologizing so much and is trying to make it up to him. He made a mistake, that is why maybe they could listen, ACTUALLY listen to each other and work-out on how to lessen that negative effect while not erasing it at all. Pride be damned if their safety is involved.
He made a mistake? bro affected him for years, apologies but then does similar if not the same shit. to the point mc's body cant function without su-ah pheromones. its understandable that mc is mad because of his lack of autonomy and is probably tied to him for the rest of his life and not only that the constant crossing of boundaries and his cry baby act is disgusting especially if you know ur friend basically hates his gender cuz he doesn't want to be seen as lesser and bros thinking of how to mark him. I would just bond with him and cut contact

I wish that Juhyeok would treat Su-ah more softly. I know that he think it is Su-ah's fault why his second gender was not what he expected, but they are in college now for crying it out loud, he must ATLEAST recognize, acknowledge that Su-Ah has helped a LOT. Having someone protect you is not weakness, it is screaming to the world that "I'LL FLIP YOU OVER WHILE CRYING MY LUNGS OUT!"