Matsumoto Tomonori wants to live in a tower. Some of the greatest enclaves have them. Tall buildings, full of empty space. High ceilings, workshops, art...the best and brightest graduates of the Scholomance are given the privilege of living in these towers. They serve the people of their enclave with magical prowess, dispensing wisdom and gifts, and in return, they get to be left alone to their work. It's the greatest thing he's ever heard. He dreams of it- at night, while he's asleep, and in danger from maleficaria, and during the day, where it sits on the same shelf in his soul where he keeps every other idle dream- if he lives long enough, they'll become ambitions.
Tomonori is the third of four children. The Matsumotos adopted their first child almost on a whim- they realized that there was a child raised by two mundane parents who was magical, and not mundane like them. They could not bear to imagine that child dying without a chance at a real life. So they did what any responsible wizards would do: they kidnapped him. They raised Tomonori's eldest sibling until it was time for him to attend the Scholomance, and he graduated with a spot in the Shanghai enclave, one of the best, biggest enclaves in the world. Tomonori might get to meet him one day- it would be nice to know his name, given how much else he knows about him (favorite color, favorite food, hobbies). Tomonori doesn't have any of those, of course; just like his parents would have wished, if they were the type to wish rather than find their fortunes. Tomonori loves magic enough that he follows their instructions to the letter, and he doesn't have those little private preferences of his own.
The second child, who Tomonori knows nothing about, died after failing to earn a slot. Tomonori wonders if his parents will let his little sister remember him if he dies in the Scholomance. He hopes not; it would have been so frustrating to remember someone who died instead of letting him get to know them. Tomonori learns as many languages as he needs to to meet basic requirements: Classical Chinese, Mandarin, Cantonese, Japanese, English (well enough that he'll only need months of tutoring, not years, which is what matters for getting spells in it), which will serve him well no matter how he tracks. Tomonori can pick up artificing or alchemy if need be; they may be dangerous, but he is smart and he is careful. They weren't able to afford a test to divine his affinity, so it was convenient when Tomonori was able to divine his own affinity- identification and detection spells like the kind used to divine affinities.
Tomonori is intelligent, careful, and more than anything in the world, he wants to live in a tower. His parents have given him the best chance the world can give to a mundane-born kid, and he's ready when the pull of the Scholomance comes.