Sketches v2: A family resemblance

I've had Mo for years... and the last time I drew her brother, I didn't draw her along with him! In fact, I hardly remember drawing them together at all!
Which is fitting in a way, because these two would kill each other on sight. 

Mo's brother, Rivett is a canon character - you'll see him in only one episode, The Mechanist (the first one I ever watched, too). He's a fun character, in that you can never be sure if you trust him. Is he lying? Does he really care about you? Having him for a brother is an awkward messy experience. 

Also some ideas I had for background characters - Energy-class riders with actual lightning-bolt hair - I'm embracing the anime-hair quality of this series wholeheartedly.