Responses
I also don't want Yahwi's character development as crazy as it sounds. Yahwi is a bad character, changing it suddenly will make everything confusing. Also, if he has character development, it's likely he'll end up with Jooin, although he was a trash character through almost 40 chapters of this series.
I'm not ready for the cliché. The second main love interest (Cain) will probably lash out, turn out to be a stalker, or hurt Jooin in some way. Then the asshole love interest (Yahwi) will have his character development when he saves the MC.
I have hope that not all Bl is the same, but I'm anticipating the worse from this.