to be honest-
i feel like this description describes "Solo For Two" its currently ongoing. Only difference is that due to trauma the main character has a lot of insecurities and a hard time accepting the face that someone gen loves him. the male lead is gen in love with him and v sweet etc etc.
another one your description reminds me of this other one but i CANT FIND IT FOR THE LIFE OF ME . i forgot the nameeee (╯°Д °)╯
its set in old europe (idk the exact era) and it has a poor painter as the main character and wealthy main lead.
I have a whole list that has similar stories to what you mention
https://www.mangago.zone/home/mangalist/796551/
Anything like this?? But with better plot or more plot focused because I know this will be smutty but story when the ml save the Mc and the Mc try to pay him back but he refuses the offer and just love him instead