So, the title sounds weird but apparently I have noticed in a few BLs where they tend to 'exchange' the physical features of the MC and the ML in their cover photos. For instance: Thriller Trainee: https://www.novelupdates.com/series/thriller-trainee/ So apparently, in the text it's mentioned that the MC had 'pinkish eyes'(or maybe yellow ones, I don't remember because I read the raws a while back) and the ML had 'red eyes', which indicates that the eye color has been interchanged in the poster. After The Abyss Dragon Woke Up https://www.novelupdates.com/series/after-the-abyss-dragon-woke-up/ So here, the hair color of the MC, who is the abyss Dragon, has been changed tk silver. It might be based off on the fact that his 'adult' dragon form had silver scales but it's mentioned multiple times that he has soft brown hair in his human form. There's also the other fact the 'dragon impersonated as human' MC is attracted to ML's 'silver' hair and basically tries to turn ML into one of his collections. So, yeah, here too it seems a physical feature has been exchanged.