Harrison and his older brother, who was also originally a follower of The Demon, were born in London in the United Kingdom. It is unknown how or why they ended up in the United States, although it is implied that they lost their parents at a young age, and that The Demon took them both in, which they both accepted, as they felt that being allied with The Demon would help them to get over their losses and to achieve their goals at the time.
Neither Harrison nor Piercy were aware that their father Mr. Provost was still alive. Much less did either of them realise that it was actually The Demon who murdered their mother, as neither of them knew at the time that Xeren and The Demon were the same person.
Before Harrison and Piercy switched to the good side, the latter had a tendency to be slightly manipulative towards the former, which is evident when Harrison started to show signs of wanting to leave The Demon and join the good side, he pushed him into remaining on The Demon's side. Piercy's manipulative ways were ceased when he himself began to have second thoughts about his allegiance with The Demon.
In a way Harrison and Piercy's relationship with one another is sort of similar to Li and Wen Yong Fa's relationship with one another as brothers. With Piercy and Wen appearing as the more manipulative ones between their brothers, while Harrison and Li appear more mature.
In some ways Harrison and Piercy's relationship was sort of comparable to Harry's initial relationship with his maternal cousin Dudley Dursley, except Harrison and Piercy's relationship was still mostly positive, so in a way these relationships are comparable, yet non-comparable.
Harrison is 12 years old, 1.45 metres tall, and weighs 40 kilograms. He was 11 years old at the beginning of the story but turned 12 on the 26th July 2017. He looks very similar to Harry Potter in appearance. The only obvious differences are that Harrison's hair is dark brown rather than jet-black.
He doesn't have a lightning scar on his forehead, instead he has a scar that is sorta partway in-between being lightning shaped and being normal. His glasses are identical to the ones John Lennon typically wore in the late 60's / early 70's.
At the beginning of the story, Harrison came across as quite devious and cunning. He initially despised happy families, as a result of losing his parents at a young age. However during the first half of the story, he has a change of heart, as the good sides of him reawaken. However he doesn't properly reform until the end of the first half of the story.
After he reformed, Harrison was shown to be quite a brave, loyal, and selfless person. He has always been considered to have a quirky sense of humour, as well as quite a big personality. Although Harrison isn't a wizard, he frequently uses magic as a reference, much to his brother's slight irritation.