SPOILERS Theory on character backstories

I think most of us can agree that the little boy MC keeps mentioning is our ML. I think there is even a part where the MC compared the ML to the boy. But then what exactly happened? Why didn't he recognize the MC?

First, go back to Ch 8 to where the ML is on the phone with one of his guys. They infiltrated the lab and looked into the Director's family history, which only came up as having 2 sons. However, ML seemed to be looking for a 'daughter' and is FURIOUS at the suggestion that she could be dead if she even existed at all.

Second, we know for a fact that MC was experimented on as a child by his own father. He had gotten close to a boy who then tragically died and was set free from his own experimentations sometime after the boy died and has been hiding his special abilities ever since.

If we assume the boy is the ML, then we have to take into consideration who it is that the ML is looking for. He seemed to not care about the Director having 2 sons. So the person he got close to was a 'girl' or more precisely someone who LOOKED like a girl and is related to the Director.

What likely happened was the MC had a feminine appearance as a child with long hair. The ML mistook them for a girl. The young ML gets close to the MC and finds out the Director is their father. The ML is experimented on to the point where he dies/almost dies and the MC believes he's dead. But the experiment is a success and the ML lives and gains a dangerous power where he devours things with his energy (as shown in Ch.23). With this experiment successful, he is then used by the Royal Family, but he is using them in turn so he can find the 'girl' he met and probably to destroy their operation.

Meanwhile, the MC is set free with his father thinking he was a failure as an experiment. However, the experiment was successful for the MC as well, making him an S rank Guide AND an A rank Esper with an absorption ability. MC has to keep his abilities hidden so his Father can't find out and continue to use him.

They both grow up into adults, which obviously such a large amount of time makes it hard for anyone to recognize each other, but of course there's more that makes it difficult for them to notice each other. The main character can't recognize the ML because he fully believes he is long dead. And the male lead doesn't recognize the MC because he remembers the person he met as being a 'girl'.

I think now at the most recent chapters the ML is finally connecting the pieces and has hope that the MC is the person he met as a child.