The Megamon Series is a series of games which are a crossover between Megaman and Pokemon. These games have Megaman style gameplay with Pokemon elements implemented. Currently there are two games in the series. The games take place in both the Megaman and Pokemon universes taking place sometime after Megaman 10 and Pokemon X/Y.
Megaman - Also known as Rock, he was originally a robot designed by Dr. Light, speculated to be simulate a son. However when Dr. Light's colleague, Dr. Wily began causing problems for the world, Rock underwent an upgrade allowing him to fight whatever Dr. Wily attacked with.
Dr. Light - The creator of Rock and an impressive inventor. He is a world renowned expert in robotics and while has been falsley accused of several crimes in his life, overall the public have a positive view on the man.
Dr. Wily - A fellow colleague of Dr. Light who was always in Dr. Light's shadow making him resent anything about Dr. Light including the robots. Dr. Wily's jealousy allowed for him to attempt world domination by creating armies of dangerous robots to take over the world. Regardless of how he got an army of robots he has always been defeated by Rock (Megaman).
Please note that as of the current games made these are the only main characters as other Megaman characters and any Pokemon characters have yet to make a physical appearance.