Left's Right; Right's Left by Han Yujoo
The story takes place on a stairwell, all in about a minutes time, while the narrators partner seizes her by the hair. The narrator had gotten caught, after running out of the apartment to try to escape assault. While she tries desperately to avoid falling down the stairs, she has a series of flashbacks about a friend who committed suicide years earlier. In this brief moment, she searches her memories for any signs she may have missed, and feels guilt for not having finished writing his story.