When the two hatched, they were stronger than most conjoined Sparks. Their parents actually saw something in them, and they weren't put to death. They lived a normal life, despite being Sparks. One day, when they were just dragonets, Aftershock suggested that she and Sonic Boom go for a walk in Woodglow Forest. They left without telling their parents, which was a huge mistake. They wandered a little too far into the darkness, and couldn't find their way back home. Luckily, an explorer happened to find them and rescue them. Ever since that happened, Sonic and Aftershock never wandered into Woodglow.
Sonic and Aftershock lived an almost completely normal life after that, and never dared to wander off from their parents again. One day, however, their parents were caught by an assassin and killed. After hearing the news, Sonic Boom and Aftershock decided to move away from their home, not wanting to be reminded of their parents. Ironically, they became explorers and decided to visit Woodglow again, but not going too far in, and this time finding it more comforting.
Boom & After's scales are a very dark gray, almost black. Their sidescales are a dark red. Their feathers are a lighter gray with red feathertips.
Sonic Boom is quite the spunky... head. They often get Aftershock into trouble for saying or doing the wrong thing. Sometimes Sonic argues with their sibling, but loves Aftershock to death and would do anything to protect her. Sonic is quite overconfident, believing they are the best head of the two. Sonic is also short-tempered and gets angry often.
Aftershock is the more quiet and reserved head. They are in control with the rest of the body, often making the major decisions in life. She argues with Sonic a lot, but still loves her sibling. She isn't as protective of Sonic Boom, however. She is quite afraid that Sonic Boom will lose his temper and release too much electricity.
Kurogami: SB and AS don't really know how to react to this dragon?? but they kinda like em?? Maybe?? Dunno??
Anoma: Sonic Boom and Aftershock are both thrilled to know that there is another two-headed dragon in Pyrrhia (that's alive, that is)