Like his friend and occasional cohort Bart Wheeler, Moraga Vasquez began teaching at Carramba High after the Clonegirls had been and graduated. However, in their relentless search for partners to rebuild their world's population, Moraga was top-tier good genetic material. He knew this, he was still somewhat resistant to being 'used as a stud'. Moraga has family issues. Lots of them. (The link above takes place before his meeting with Maroon.) Getting him to 'give up the goods' as it were was a bit tough. But in the long run, he recognized that Maroon and he were quite well suited to make babies.
Mercy... is hardly merciful. At least toward the Combine and invasive animals anywhere around their home on her mother's Earth. She spends far more time outside than in, and unlike her father, Mercy prefers to 'love em and leave em' - even to the point of having two children of her own, before her eighteenth birthday. Auntie Lilac takes care of those children, by the way. Mercy is not a great mother figure. Though she is quite intelligent, she's much more of the physical type and uses her smarts to take advantage of her situation, not to become erudite.
Mercy is, in a word, feral. She has strong command over flighted animals, which would be great if she ever wanted to follow her father to Zekira. On her world, though, and in Carramba's teaching situation, it means she's occasionally responsible for sending flocks of pigeons (or flitters) around the lunch court to deliver 'messages' in the form of poop, or to take temporary control over even strong-willed people who have avian features to get them to do things for her.
While she recognizes that these things aren't... really very friendly, she wouldn't just go out and mess with people haphazardly. Her father taught her about 'not crossing the wrong people' - and he can point to his own background, as well as numerous members of her extended family, for proof. She's not stupid, she learned that if she was going to piss someone off, it was first for a good reason, and second that she'd win a fight with them if it came down to it.
Indeed, Mercy ... is not at all her namesake.
Mercy's dragons are both Whiptails, domestically bred from their homeworld, and share the same features found among those already running around the Rookery. They were both made by DragonsAndVideoGames on Deviantart, they have no specific parentage nor are they related to any in the Rookery, though they share similar coloration and may be mated as a pair eventually.