A/N - A wrong path taken starts with a single mis-step.
Marvin had a brother. A twin actually. Anthony "Anti" Blake. The nickname started when they were really little and the boys couldn't quite say 'Anthony', and it stuck.
Anti was always more confident than Marvin. Loud, rowdy, and stubborn as a mule. He was that child who would deliberately not do something just because you told him to do it. Marvin was less so. He was still stubborn if you pushed him, but mostly he was quiet, and kept to himself.
Though they were different and ran with different friend groups, they could always count on each other to be there. Marvin never thought twice about swearing on his life that Anti was with him whenever a teacher came sniffing around, and he never had to ask Anti to have his back when some dicks tried to pick fights with him.
It didn't last.
Once they hit their teens, Marvin started having magical 'accidents'. He refuses to explain any further but insists that no one suffered any permanent damage. It was a hundred percent an accident and everyone was made whole in the end. Everyone waited nervously for Anti's powers to manifest, the two of them being twins and all it was kind of expected, but they never did.
Anti grew into a typical troubled teen. His grades weren't great, his attitude stunk, and more than once he was brought home by the police. It's a miracle he was never charged with anything. Their parents meanwhile were more than a little preoccupied by the whole magical issue. It's not exactly easy to control, but with a good teacher it was their hope that Marvin would not cause any major incidents again. The trouble was most of them were ridiculously superstitious.
One tutor refused to teach on any day with an 's'; another took one look at Marvin and simply called him a hopeless case; the majority though refused the moment they found out about the magic-free twin. A grave omen, they called it. A sign of things to come.
Self-teaching was Marvin's only real option, which honestly was kind of useless. Magic's a difficult skill that takes more than time and practice. It requires specialist knowledge passed down through generations of magic practitioners. It really isn't a skill you can just learn from a book, but the family had run out of options at this point. It was the book, or nothing, and they couldn't afford another incident.
One day, one awful hideous day in their final year of school, Anti came into the living room while Marvin was studying. The two of them had grown further and further apart since the magic shit started. Not only was Anti considered lesser, Marvin's magic consumed a large portion of their parents time and it was almost like he wasn't even there. Anti hated that Marvin had magic. He never said it, but he didn't have to. Marvin knew.
They'd started arguing. Marvin doesn't remember what about, but at this point, does it really even matter? All that really matters is the argument got heated. Anti shouted, Marvin shouted. Anti grabbed the spell book from Marvin's hands and threw it against the wall, screaming at him, and Marvin screamed back.
All he really remembers of the moment is an intense flash of blue and excruciating pain, as though he were sliced through by a white hot knife. A great ripping and tearing at the very edges of his soul.
They both screamed before everything went dark.