Are there any novels about the female protagonist being a physics genius and the male protagonist loving the female protagonist in his previous life?

The female lead was a physics genius who seemed to be studying theoretical physics. The male lead loved the female lead very much in his previous life, but did the male lead have a mentally ill cousin? She destroyed all the people who were close to her brother or her brother liked, so the female lead was killed by her later on. She hired a murderer to kill them in a car. The male lead also died for love. After his rebirth, the male protagonist tried his best to change everything. It was a heppy ending. The cousin destroyed everyone who tried to get close to her brother, including humans, animals, and plants. The girls who tried to get close to her brother were also killed one by one. Some were raped, some were knocked over, and so on. It was not until the end of the novel that the male protagonist confirmed that she had mental illness and sent her to a mental hospital. He suspected that it was hereditary because the cousin was her mother (or her aunt?) She was also mentally ill, and he had taught her how to hide the fact that she was ill and make others think that she was normal.