Responses
From what I saw on the spoilers...
When he got his sight back, mc left the mansion, so then the ml went to go and find her. Since the description match the mc's sister, ml thought that she was the one that helped but then he felt that it was not her, then sooner or later he found mc (i dont remember in full details but yeah)
Ahhh I think I know where this story is heading. She described her sister which will lead to him & the sister being engaged or a couple. He will either get his eyesight back see her sister and treat her really well thinking it's her. Or something will happen & he will meet her sister and believe she was the one who took care of him. Either way we go him & the sister will have a thing and she will be devastated because she lied about her appearance. It'll take awhile before he notices the real person and the truth. I'm hoping not because then it'll be a typical plot.