To inject heroine into an erect penis just before orgasming. The effect is both explosive and calming. The combination of stimulant and downer exponentially increases the pleasure of each.

When some little bitchboy is acting like a little tiny pee pee poo poo baby and messing up the group plans.

Smacky Jack is the act of shooting heroine into a vein in the penis just before orgasming. The combination has an overwhelmingly explosive then soothing effect.

When heroine is injected into a vein in the penis while a man is orgasming. It is intended to exponentially increase pleasure.