..... if you needed anymore proof of the inconsistent writing behind this story, reflect on this. When RWBY first used her Silver Eyes, it caused this damage to happen to Cinder, mind you Cinder wasn't part Grimm at the time she 100% human, who just so happened to recently inherent the full power of the Fall Maiden. According to the "Grimm Reaper", however the Silver Eyes only harms Grimm... .... chew on that for a minute.

Selvokaz said:

..... if you needed anymore proof of the inconsistent writing behind this story, reflect on this. When RWBY first used her Silver Eyes, it caused this damage to happen to Cinder, mind you Cinder wasn't part Grimm at the time she 100% human, who just so happened to recently inherent the full power of the Fall Maiden. According to the "Grimm Reaper", however the Silver Eyes only harms Grimm... .... chew on that for a minute.

That plot point, to this very day, has not been made clear. We have no idea of whether Cinder's injury was due to her being a Maiden or anything relating to Grimm. Fans have often said it was the Grimm parasite she keeps with her; while probable, it's a convenient excuse after two years. Cynical as this sounds, once this point finally gets touched upon, chances are it's because the writers finally remembered how confusing it was to begin with. It's like Schrodinger's Writing.