This manga plot in summary: Because the female characters treat the protagonist poorly in their past, out of guilt, they became horny for him. Also, everyone is beyond stupid.
The girl's ambition is pathetic. Does she have some kind of inferiority complex with other people's talent? Without competition, you'll be stale and stop growing. Unlike her, other people don't have previous reincarnations like Avatar. Just pure talent, hard work, or both.