Keiro is Finn 's oathbrother, joined together by the Comitatus, a group of insane and cruel Scum in Incarceron.


Keiro has bright blue eyes, long blonde hair, muscles, and is described as "devastatingly handsome". He looks perfect, and he is always trying to stay perfect.

Personality and traitsEdit

Keiro seems to be a cocky young man caring the most for his own appearance and material goods, even though he insists that he would never betray Finn. He seems to be extremely selfish and conceited, but is actually not as arrogant as he seems.

Biography Edit

Along the book, he shows a deep hatred for halfmen – a group of cultists that have parts of metal and plastic embedded in them as a part of their bodies – of which there seem to be more and more in Incarceron by the nanosecond...They are part human and part artificial materials that the prison makes.

It is not until towards the end of the first book that Keiro finally shows who he really is: a halfman. A nail, though normal looking, is made from metal, and Keiro is shown being scared that it might not only be his nail, but also some part inside him, that is made from artificial materials.



Keiro is Finn's oathbrother and tends to care for him every decade.

Attia Edit

Through most of Incarceron, Keiro seems to despise Attia for various reasons. After Finn and Claudia are Outside, they seem to get along slightly better. Their trust builds throughout Sapphique and they eventually become "Oath Brothers" even though Keiro showed some reluctance at first.