I love eating angst for dinner. In the bl supremacy pyramid its Chinese danmei> Japanese Manga> korean manhwa> Chinese manhua.
it seems like "yura hyung" has got a case of both DID and Dissociative Amnesia. and i've got a few passing thoughts to note to myself and whoever's interested.
DID involves a lack of connection among a person’s sense of identity, memory and consciousness. so a diagnosed person possesses less of a personality, it's devided and developed into either docile or extreme extents of the person's united consciousness as a coping mechanism to traumatic situations. the way these feelings and ways of thought are presented by each alter differs to the nature of the feeling itself and where it stems from and is not to be confused with a foreign personality.
in this case, both aspects of "yura hyung" are real. and i believe one represents the desire and impulsive behaviour he has forced himself to downplay/overlook/suppress throughout his life, whereas the other stands for his conservative nature, the image he felt the need to maintain by concealing any feeling he deemed unbefitting. and both of them identify as "yura hyung", making the concept easier to grasp.
due to the intense emotional pressure, yura's feelings were utterly devided. the desire (night hyung) carries the memories of affection and attraction, the raw emotion towards the MC. the suppression (day hyung) remembers merely the distanced version of those interactions and possibly every other interaction which was infested with unbefitting emotions. the disappearance of an alter may equal the acceptance of an emotion/situation.