Seven is a hairdresser on Chicken Island with amnesia, a pair of scissors and the worst assassination record in the business. He takes contracts to pay the bills, fails most of them in increasingly stupid ways, and slowly discovers that the reason he cannot remember anything is far heavier than the comedy suggests.
The animation is deliberately cheap-looking and that is the joke: flat shapes, rubber limbs, gags that run on timing rather than detail. Then a fight starts and the same style turns fluid and genuinely beautiful, which is why the series became the first Chinese animation to break through with Western audiences at scale.
Watch it for the comedy, stay because the backstory arcs hit harder than a show about a barber with scissors has any right to.