I read this a very long time ago so I don't remember much but I'll be really grateful if a...

I read this a very long time ago so I don't remember much but I'll be really grateful if anyone could help me find this.

So MC takes part in some horror game(?) or works as an assistant in this mansion. MC keeps on stumbling over weird stuff and is caught off guard over and over again. The ML is dead and has a butler to help him around the place. It's some sort of an amusement park. And it was probably that the MC was dealing with some financial issued with her father. They probably had a horror house of their own but it wasn't working well. And there was some cash prize involved. And i remember one particular scene where the ML was playing a piano.