How to identify those inherently bad people?

They are indifferent to others' difficulties, and may even take the opportunity to step on them;
all relationships are driven by interests, showing enthusiasm when useful and immediately distancing when useless;
superficially friendly, but behind their back they sow discord and play both sides;
once problems arise, they always blame others and clear themselves completely;
they can't stand others doing well, secretly or openly suppress them;
they are also good at using morality and emotional manipulation to bind others, constantly demanding while making the other feel indebted;
people rarely remember their kindness, but hold grudges over minor annoyances;
they have no bottom line when it comes to interests, capable of lying or even betraying others;
their entire being is filled with negative emotions, habitually complaining, dragging those around them into exhaustion;
and they often speak grandly and make promises easily, but never truly follow through.