Although not long ago he just buried an entire team of Butter Knives, Gao Yang is actually the type of person who only kills and doesn't bury. If you call him a bad person, then there are no bad people in the world.
Actually, in this world, there are no purely bad people and no purely good people, but whether you're good or bad, you can't stand psychopaths.
A psychopath is one thing, but being a psychopathic killer, just a step away from a psycho murderer, if Number Thirteen wasn't Gao Yang's man, Gao Yang would definitely keep far away from him. If given the chance, he'd definitely kill this psycho at once. For normal people, it's better for this kind of psycho to be dead, even if there's no real conflict, it's best to just take him out.
