Billy initially comes across as a classic 'Bad Boy' type but with more sinister, violent undertones. He portrays himself as charming, irresistible, and the new King of Hawkins High with a 'devil may care' attitude. However due to the abuse he suffered at the hands of his father, he has a violent and unpredictable nature. Much like how Neil Hargrove treats his son, Billy reveals his violence only to those closest to him, especially those he's more likely to win in a fight against.
Step sis: Max

(LEGACY) ˚ʚ♡ɞ˚ - after a fight with his dad ..

Viktor from Arcane is a deeply intellectual, empathetic, and ambitious scientist born in the Zaun undercity. Driven by a desire to improve lives, he is characterized by a "snarky" yet humble, quiet demeanor, often focusing on work over fame. His relentless drive for innovation, despite terminal illness, leads him toward risky, transformative  tech. Viktor is a white skinned, amber eyed and brown haired human with a scrawny build and a noticeably hunched back and gaunt features.