Bonnie has a big impact. Her being away gives Vincent and Jules a place to take care of their bloody situation. If she was home, they couldn't have used her house.
Another possibility is that there is a villain who has a plan to disrupt Kim's life. The villain makes Bonnie absorb Kim's traits as part of a devious scheme, thinking it will cause chaos between them or somehow weaken Kim.
Well, Geralt might die as a result of a powerful curse or magic. Maybe he angered a powerful sorcerer or witch who cast a spell on him that he couldn't resist. This could be a slow and agonizing death as the magic takes its toll on his body and mind. Another possibility is that he sacrifices himself for someone he loves or to save the world from a great evil. He might put himself in harm's way knowingly, and in the process, lose his life.
Superman's death in comics is often a result of epic battles or selfless acts. For instance, he might face an opponent whose power is just too overwhelming, or he might give his life to prevent a major catastrophe.
Gwen's death in the comics is often a result of a tragic and complex event. Usually, it involves a confrontation with a powerful villain or a series of unfortunate circumstances.
Well, Loki's comic deaths aren't straightforward. It could be as a result of clashes with other superheroes or from cosmic events that he gets caught up in. The circumstances change from one comic series to another.