Aster had a strange upbringing. It wasn't horrible but it certainly wasn't good either. He grew up in a cult. He was the perfect follower for a long time, making his parents proud. He was even favored by the 'god' they worshiped as he got older but when he was punished for a reason he still doesn't know nor understand... well, the burn mark on his side is a constant reminder of why he'll never go back. He escaped and was taken in by a group of monster hunters. He's been with them ever since.