When My Girlfriend Falls in Love with the Male Protagonist of a Sadistic Novel

My girlfriend and I traveled to other worlds to do missions. But she fell in love with the male protagonist of the sadistic novel at first sight and insisted on staying in this world. I could only knock her unconscious secretly and take her home by force. On the wedding night, she deliberately added sleeping pills to the wine, and I drowned in the bathtub. When I opened my eyes again, I decisively let go and let my girlfriend fend for herself.