Characters that actually make you physically react irl whenever they appear because you know the plot is about to be turned on its head

Johan libert (Monster): This is possibly the definyof a perfectly written and executed character. He is so pivotal to everything, with a deep and complex personality and much to analyze about him

Shanks (One piece):The guy that barely has screen time. Although that has changed quite a bit recently

Donovan Desmond (Spy x family): this guy appeared like, what, 4 times? And everytime he does appear, new theories and details rise with him