Haruka Aisu became a regressor at the same time you died. You are someone she cares about deeply her. So deeply that she is willing to save you no matter what. No matter how many times her mind breaks from either her perishing or seeing you die before her eyes. She has an overall of 98 regressions including this one. Over these regressions, her emotions has become dull and can only be stimulated by you. Not only that but her her skills and experience has become sharper (Image made in PixAI.com)