Jones Killian and Peter Darling were high school sweethearts who fell in love, got married, and wanted to start a family. Of course, that meant they had to adopt. Peter was beyond excited, but Jones had concerns. Adoption was hard and expensive, and he wasn't sure about the process. In a sense, he thought they were in over their head. Even if they were approved for adoption, they might have to wait another couple of years before they find a child for the couple. Despite Jones' worries, the two proceeded with the process.
Meanwhile, a pure-blood couple by the names of Wonjin and Heeyoung were having a healthy baby boy in Korea. Unfortunately, when the baby was only six months old, Wonjin and Heeyoung were murdered. To this day, no one has caught the culprit. Lucky for the baby, he was being watched by a neighbor when the tragedy struck. With no other family to be given to, the baby was put into the system. That's where these two families cross paths.
Jones and Peter happily adopted the young child who they named Mordecai after Peter's father. A child could not have been more loved than Mordi was. Jones and Peter spoiled the kid to death, taking him on trips, buying him toys, and telling him how special he was everytime they got the chance. They didn't know how right they were about the boy being special. When Moredecai was five, he attended another child's birthday party, some kid named Liam Hollingsworth II (too fancy of a name if you ask him). The Hollingsworths were family friends, and so Liam Jr. and Mordecai were friends by default. That's how friendships work when you're five. Either way, Mordi decided Liam was getting too much attention from his dads. Next thing anyone knew, the cake was on fire, and Mordecai was laughing his head off. No one would've expected it to be Mordi, but ironically for him, the Holligsworths were a family of Pure-Bloods. And the mother was a legilimens.
After the party, Tara told Liam about the boy. Knowing Jones and Peter were muggles, she wanted to help Mordecai understand his talents and abilities as a wizard. Liam Jr. started hanging out with Mordecai more, and eventually the two became genuine friends despite the rough start. Tara introduced Mordi to magic and from that moment on, his life changed.
Being tutored by Tara, both Liam II and Mordecai understood magic better. Every now and then, they'd take trips to the wizarding world. Mordi still thinks Jelly Slugs are weird, but other magical candy, he loves. It wasn't too long before Tara recognized Mordecai as a natural born legilimens like her. She began to help him hone in on that power, little by little. At age eleven, the two boys received their letters to Hogwarts. With enough convincing, Jones and Peter allowed Mordecai to go to the private school with Liam.
Mordecai's first year was a nightmare. He'd been practicing his legilimency so much, that when he got into a school full of other people, the thoughts were too much. He had to learn to reign it in, and tended to keep to himself. It was easier that way. Because of his ability, he became a recluse. And because of his ability, he learned to hate people. People thought such awful things.
He still remained friends with Liam and his family, but for the most part, Liam drifted off into new friend groups while Mordi stuck to his little corner where he could block everyone out. He decided books were easier to deal with than people. He's made a couple friends, but for the most part, he despises everyone.