A theory based off of the new Wonder Woman movie, Harry Potter, and Percy Jackson.

The first bit came from Uma_Of_Light. I made the rest though. cupcakesandcocoa also witnessed the creation of this theory.

So Lupin was actually Aries sent to keep the trouble making set of Wormtail, Padfoot, and Prongs in line as punishment from Zeus. He was sent back to help Harry in the battle of Hogwarts and he had grown to love Prongs and helped his son to defeat Voldemort by fueling his fury against Voldemort. Voldemort is especially powerful because he is the demigod son of Zeus. Ares wanted to stop him, so he took a mortal wizard form. However, Zeus had forbidden the gods to interact with the mortals. So Zeus curses him to turn into a wolf when under the full moon as long as he stays with them. Later Ares was killed as Lupin. It hurt a lot, and a hatred grew for the boy he had risked his life for. Then there was Percy Jackson. When Ares met Percy, he was reminded very much of Harry. Ares didn't actually hate Percy. He was scared of getting hurt again that he though it was better to try to hate him then risk the same pain he had once felt.

So Ares doesn't hate Percy. Yet he doesn't like Percy. It turns out, Ares is scared of Percy.

I think I like this better.