My metabolism is moderate, but I know people who have ended up fat, and I always skip breakfast (and sometimes dinner) because I don't wanna be chubby...
NEVERSKIP
BREAKFAST
ever.
This is why you have such pinchable cheeks, little girl.
Even on days that I have only 300 calories, they're all in the Breakfast meal.
My metabolism is rather high, but my genes are not built to be small. All the men in my family are built like tanks. My Grandfather played College Football, my Uncle did College Wrestling in the largest division.
I remember when I was really little and some kids were playing football. I hated sports, but they needed me to even teams so I reluctantly obliged. Round after round I would walk with 3 people clinging on me to the goal area. I was twice their size, independently, and a year younger than them.
Not only that, but I gain muscle mass easy. If I actually do get up off my ass and work, I start to notice gigantic bulges in my arm in a matter of days. I've only worked 21 hours since Saturday at my new job, but I can feel definition in my forearms already. It's great.