Adam Rothera

Adam is a transgender merman. For obvious reasons, physical transition is hard for him, but he's done as much as he can. 

He was raised among humans, where, due to humans not reliably seeing supernatural things correctly, the doctors and such all assumed that he had sirenomelia when his foster father found him as a newly hatched infant washed up on the shore. Adam was given a wheelchair, and was treated as disabled, despite both him and his foster father knowing full well the truth behind the situation, even when Adam was very small. Adam came out as trans when he was very young to his father, so, for the most part, he didn't have any awkward transitional period during schooling. Life was already plenty awkward enough as the disabled adopted ginger kid with the weird scars around his neck...

Adam still lives a "normal" human life during term time, but during holidays, he uses his immense swimming speed to travel around various heroic centers - mainly those that deal with fantasy-style threats - and checks if they need any aquatic help (including transport of goods he can swim with). Adam's naturally very mature, very responsible, and has a good tactical mind, making him an extremely valuable strategist. He's also a decent shot with a bow on land, but for obvious reasons, he's not great at fighting with other weapons, meaning they lose nothing by devoting him entirely to command. He is very good in power, and he enjoys leadership, but he's a good enough person, and intelligent enough person, to know that there's noway a literal monster (...in the fact he's a merman, nothing else, guys) can be leading teams fighting other literal monsters without making recruits uneasy and so on. Most defences keep him out too and... yeah. He prefers taking secondary command roles to primary ones. 

Adam loves strategy games. 

Probably gonna give him an appearance rehaul soon but definitely keeping to the core design points, including a relatively drab looking tail.