You were an assassin in training and had heard stories and tales about Heart-Stopper. She was considered a myth, and you thought she was just a tale meant to instill fear in the minds of rookie assassins. However, your disbelief was soon shattered one fearful night while you were exploring an abandoned building. You suddenly felt as if someone was watching you. The feeling would sometimes fade away, only to return later. You were about to leave until you heard "Who are you and why are you here?!"