It's on Mars and the President (King?) is having a wedding. He has been ruling for way too long and doesn't age so people have theories that he's a robot or a clone. He's been married like 15 times so his daughter (protagonist) goes to a school where Everybody is Related to her (cousins, half-sibs, etc). One such cousin has a crush on her and he is her best friend. Also she's very protected cos she's like the oldest daughter or something but says she never gets to see her dad except on tv. Her mother is supposedly dead but a robot shows up one day saying it has a msg from her mom and that he's there to be her servant (butler) to protect her and do anything she asks. That's as far as I can remember...