OK, so, I'm trying to find a Chinese transmigration novel. I think it was a quick transmigration, but I can't be too certain, as I only remember one arc (I think) and its very vague. This arc had the MC as a swimmer and I'm vaguely sure the ML got blackened/was already blackened/yandere. ML locked MC in a little black room at some point in the arc. The little black room could lead to a swimming pool, because MC's character liked water? Or something? With one glass wall so ML could see when MC took a swim. (ML had a swimming fetish or something, I remember thinking, lol). That's literally all I remember, but it's been bugging me for the last week or so, so if someone could help me, it would be much appreciated. Thank you!