Looking for series with ruthless main characters

Think of Kaz from Six of Crows, that’s what I’m looking for. Male or female!

I’m sick of arrogant main characters (looking at you Celaena Sardothien) that the author continuously says they’re the best at something. I want ruthless, will kill to protect the people they love or get what they want. I need more books with the characters like Kaz Brekker!!!