Okay so I know that he’s cannonly a muggleborn, but i’ve actually made him a half blood.  Basically his mother is a muggle and his father, a wizard but his father died when his mother was pregnant.  So he’s been brought up in a muggle home and went to a muggle primary school, and hes extremely proud to have muggle blood in him.  He realises the danger, but he’s so blown away by having been brought up by his single mother who was nowhere near rich, and didn’t have magic to help.  

He’s a genuinely good person, and a gifted wizard.  I think at the end of the day he just wants to get good grades and give his mother a better life in her older years, and get into the ministry for a career.