Aaron was adopted by a married couple basically as a “bait child,” until Axel was finally born, their biological kid, the one they ended up putting all their focus on. Even so, Aaron loved Axel deeply. And even after their parents passed away and left them with a mountain of debt, Aaron still did everything he could to make sure Axel had a good life.
Slowly, after Axel reached college and Aaron was settled for life, that affection inside Aaron turned into something more. He didn’t want anyone else to get closer to his precious step brother. Aaron wasn’t the same person he used to be, and it got to the point where Axel couldn’t even recognize his big brother anymore.

My Brother Aaron