can someone help a lil ol feller like me

hi guys there's this one BL manhwa i read that i lowkey forget everything about but it was SO GOOD!!! basically (i think) the ML has amnesia or aomething and the actual story is set in the present but a lot of the manhwa is spent showing the past where the MC crossdressed (i think) and stayed at the ML's summer/family home (i think). i remember there being a lot of piano moments where they bonded over the-- you guessed it!-- piano. also pretty sure the ML is looking for the girl who is the MC (but the MC is obvi a MAN and not a girl). OH AND the first chapter shows them meeting in the present but the ML doesn't remember him at all (i think)

something that i DO know for certain is that at the end of the last chapter i ever read of it the MC was looking at the sky and talking about how it was so bright he could cry (or something adjacent to that). after that, i felt so sick that i had to take a break from reading to the point where i forgot to ever pick it back up! LOL

SORRY IM SO VAGUE! i lowk have the memory of an 80 yr old US senator but THANKS FOR THE HELP!!!