after (one's) blood(redirected from after their blood)
after (one's) blood
Seeking revenge on another person. He hit my car, so I'm after his blood now.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
after your blood
If someone is after your blood, they want to harm or punish you, because you have done something bad to them. Adam has upset Broderick, who is after his blood. The entire street-gang network of New York is after their blood.
Collins COBUILD Idioms Dictionary, 3rd ed. © HarperCollins Publishers 2012