My Analysis:
OK, STEP 2, after bringing out of the brightness, I duplicate the layer and created layer 2, move upward one character up and use overlay.
That is 1st place Kokoro now overlapping unknown 2nd place
Unknown character.
2nd place unknown overlapping 3rd place phase 4 etc.
Now here is the result. Notice in the 1st place, Kokoro now shows a full perfect Kokoro without any other character face?
If the unknown is another character, it would have been mixed like the rest of the characters.
See how the 2nd character's face now is mixed with phase 4....etc. etc. Same as the rest.
(The 10th character has no face overlapping it, so skip that one).
So conclusion. It is in fact Kokoro. She does has her hair down a bit on the right side, since the 2nd place darken it, it become hard to see. But
in fact is her Kokoro, no doubt. False alarm people.
1) Before overlapping the character image:
2) After overlapping the image one character up: