I was pissed off about that too but then I realized she was just gonna die anyways. triangle guy seems invincible so far. obviously she could have taken everyone else several times over, assuming he didn't stop her, but either way he would just use one of his reality hax cards and kill regardless. it was either die meaninglessly, die meaninglessly after killing a few of his subordinates including a manipulated child, or give the child one small act of mercy and hopefully teach them lesson then die slightly less meaninglessly. It makes sense for person like her to pick the third one.