Jack
He charged the other man. His head connected with the other man's groin and they both fell. Jack jumped to his feet growling. The other man lay on the floor with his hands on his groin. Suddenly there's a sharp unexpected pain between his legs and he falls over the other man. Then he's picked up and thrown landing on the floor rather hard but all he can concentrate on is the pain between his legs. The other man is helped up by his friends and the taller of his friends leads him away. The shorter one turns his attention to Jack.
Jack growls trying to seem menacing but he's in too much pain and ends up groaning. His father had never been this cruel to hit him between his legs. This pain was all new. The man picks him up by his hair. The new pain is enough to drag his mind away from the pain in his groin and he growls. He struggles against the other man's grip. As he's struggling the taller man returns. The man holding him pulls out a gun and aims it at his head. Jack freezes he glares at the man.
"I will pull this trigger"
"Dean"
"He hurt Cas, Sammy"
"I know Dean I was there"
Jack may have been shorter then all three men but he wasn't weaker. He pried the other man's fingers open and dropped. The man tried to shoot him but Jack was faster. He was on Sam's back and choking him. Dean tried to pry Jack off of Sam grabbing his hair but Jacks grip was too tight. When Dean pulled Jack Sammy came with him. Dean pulls his knife and holds it against Jack's throat. Jack climbs off of Sam's back and grabs Dean's hand with the knife. Jack slowly drags the knife across his throat.
"If you're going to threaten me with a knife you better show you fucking mean it!"