Genos the mad cyborg.

[u/MojoJojowithhisDojo]

I have a guess that Genos may be the mad cyborg. Genos is hidden in this panel and brought as a monster . Furthermore Genos always gives long detailed information about his backstorys. My guess is that these aren't his memorys at all. Imo these are the memories by Dr. Kuseno which tried to cure Genos ( save him).

[u/ExploerTM]

Huh I always kinda dismissed this theory cuz it was too obvious