Help me find this

The story is about parallel world. In 1st World, ML is obsessed with Fl but she dies later. And ML i think dies and goes to 2nd world. In 2nd world, FL is the obsessed one and Ml hates her. He sleeps with different girls and even tries to kill her multiple time. 1st world ML now in 2nd world ML bodies tries to mend the relationship with FL now. Fl is also pregnant.