I saw it a long time ago when there was dramafever and the truth is that I don't remember much about the series but I'm almost sure it was Korean. Well here is what I remember: A girl wants to marry a rich man after she meets a friend from school who married a rich man after being a secretary to her husband's mother. I think the girl has a job that has to do with clothing design. So the male protagonist is a rich boy who is in a fight with his father and that the girl does not know that he is rich until almost the end, the girl first wants him out of interest. Also, the boy is like traumatized with an ex-girlfriend who left him for being poor so in the end when he realizes that she is using him, he kind of disconnects from reality. There is a scene where the girl dresses up as rich and she learns a lot of facts about the rich people who go to the party but a boy throws her a glass of wine or something like that, Then the protagonist defends her by doing the same to the boy when she leaves. I also remember another scene where the boy's father goes to the pets company setting up a project (very funny) and another when the boy is the boss of the ex-girlfriend's husband and goes to her house for dinner.
90% of Korea dramas have this plot. I will give you one: It might be this https://mydramalist.com/1194-soulmate I thought I found another one but it is a different plot https://mydramalist.com/1228-wedding Maybe look at the male lead's dramas, he seems to be in that type of drama alot You have series with Temptation in the name too Such dramas might fight Best of luck to you I tried looking and failed but maybe one of this will inspire you http://web.archive.org/web/20210125...1/top-30-rich-guy-poor-girl-korean-drama.html