OMG SAME. this adaptation lowkey feels like a smutty fanfic and not like an official adaptation. Like no the ml and the mc are respectful of each other and do not crave after each other in the sexual intimate way until so much later. I would have preferred they kept all the cute moments of them in that trashy place they are living in but no the artist just had to put unnecessary sa. It’s so annoying i want a new adaptation that’s done correctly.
Okay you asked for extreme major spoilers so here they are:
It’s kinda complicated but uju hyung is the mc. The mc falls into a time paradox and goes back in time and suffers some serious wounds so he can’t talk really well and his voice is messed up. Thats why ml couldn’t recognize him. Ml ends up going back to the past and brings mc back and tells ml that he is uju.

ugh I'm so mad they keep forcing on this narrative of ML just kissing MC outta nowhere when he literally didn't even kiss him not once until they were together (not to mention that fuckass reverse guiding that doesn't happen until after ML gets critical and MC is the one I who does it, and he's so guilty about it.)