Kagerou Wiki

Karen was the clerk that Red was raping in the back refrigerator room of the gas station Kano walked into when the two first met.  After killing Red with his own gun while Red was distracted by Kano, she escaped into the night before the gas station collapsed.

Kano believes her to still be alive, having appeared in a newspaper later, but she seems to be trapped in a glass cylinder in Kano's mind, fusing with some sort of tentacled horror and unable to kill herself to escape.[1] Kano runs away in horror at this and is later attacked for failing to help her out.[2]