Roleplay for me is fluid and so I like to keep Mamoru's back story and main personality kind of open until I understand what the RP genre is going to be. He can even be totally human if the RP calls for it. I do have a backstory for him however and if I am using it I tend to split his character between two different stages in his life. When he was younger and still lived in shangri-la with his father, his personality favoring his human side. Then when he is older living on his own, his personality favoring his godly side.
As a younger more inexperienced demi-god he is a free spirit type, always looking for mischief to get into. His demeanor is mostly Chaotic good, innocent to a degree but still has a bit of darkness. If he doesn't get his way he can be a brat, but if he's pushed to far he can become another person all together. When he's unfamiliar with his surroundings he can be shy or timid. Getting along with people comes naturally to him though and he is always looking for more friends. - As an older more experienced being that had been split between two worlds his psyche has followed suit somewhat. Known as the mad god in some timelines, his demeanor comes off as more bipolar then before. His softer human side is often shielded by his harder, prouder godlike persona. Paranoia has made him harsher and colder towards most races that seek power and control. Years of watching wars and taking place in some of them have quieted his more gentle nature that loves and cares for all things equally, though it is still buried somewhere.
More info: Mamoru is a demi-god birthed by his human mother from the seed of his father. One of the 7 gods of destruction. Violence. A large panther spirit. His parents reside in Shangri-la but Mamoru can usually be found on earth. His parents have wanted him to take over for his father but the issue is he never felt anything like his father. He can be rather weak and shy, instead of powerful and strong. Kind and passionate when he should merciless and brutal. He has had many fights with his parents even though he still loves them. He feels like a failure and tends to let weakness get the better of him. That doesn't mean he is really nothing like his father though. When pushed too far his natural inherited rage can consume him against his will. As he aged he separated more from his father and eventually left all together after a large fight. In his later life he mainly drifts from one adventure/battle to the next. Growing stronger and more willing to take his father place by force.