Pull his pants down and uppercut.

You quickly grab his waist and pull down his jeans, much to his confusion.

He is wearing nothing but tight black boxers, his balls even more exposed now.

You swing your fist upwards with intense ****, smashing your fist into his mighty boxer covered balls with a sickening crunch.

His big balls crush against his pelvis as you keep your fist there to intensify the crushing damage.

The poor zombie boy just stands on his tippy-toes as your fist presses mercilessly into his green nuts.

You finally remove your fist and let his balls pop back into shape, before he falls onto his back, passed out.