"Balls-free" orgasm (CBT for males)
 

For this dare, you'll need: a masturbator (Fleshlight or similar), a string/rope, any balls attachment (parachute, stretcher, weights, but also just a piece of string).

Kneel on the floor. Mount the masturbator in front of you (in "dick height") and the the string to anything behind you. Now you're gonna attach the string to your balls so tight that when you're on the limit of feeling pain, you barely touch the toy in front of you with your hard dick. This means you only reach inside with your balls in pain. You're only allowed to untie after you cum.

SAFETY: Do this on the floor! Never try it on your bed, table etc., or if you fell down, you would very likely damage your balls. When you kneel on the floor, even if you collapsed, you wouldn't put any significant weight load on your balls.

Damn this sound so creative!