McAiken is a pureblood, born to parents James McAiken and Sarah McGonagall McAiken. He was born in the family home in Elderslie, Scotland. His Scottish Clan is under the Coat of Arms and tartan of the Stewart Clan. He prefers to wear the Black Stewart tartan, which he does regularly instead of a set of full robes. His kilt is not fitted but is in the older style of the one wrapped piece of tartan fabric.
In 2036, McAiken entered Hogwarts and was sorted into Gryffindor. He excelled in Transfiguration, Potions, Charms, and DADA. He was also the Keeper for his house team. He knew both Gideon Prewett and Kobus Hendrik while at school, although they were younger. His aunt, Minerva McGonagall took keen interest in his studies from the moment he entered Hogwarts. In his seventh year, he assisted in her personal research and in her first year classes.
After McAiken graduated, he was accepted into Auror training. He complete all but the last 6 months of the training before the Ministry asked him to become part of the Department of Mysteries. While there McAiken worked on Transfiguration Research and Experimentation.
He holds several magical patents on new objects he developed while working for the Ministry. He returns to his ancestral home during summer breaks.
McAiken was a strict but fair teacher. He require things to be serious when the need be, but enjoys humor and laughter very much. He is a keen follower of Quidditch. He has all the qualities a Gryffindor student is known for: bravery, loyalty, knowledge, and others.