Rubik's Cube Versus Penis

The joke uses a double meaning of the word 'harder'. In the context of a Rubik's cube, 'harder' refers to the increased difficulty of solving it the more you play with it. But in the context of a penis, 'harder' is an obvious reference to sexual arousal. This creates a humorous comparison.

• Penis
• Difference
• Sexuality
• Play
• Body
• Harder

• Why do men find it so difficult to solve puzzles after taking Viagra? Because they just keep getting harder and harder!
• Do you think you can solve a riddle about my penis because I don't think you can... It's too hard.
• What's the difference between a dick and a rock? One's hard.
• What do Rubik's cubes and melons have in common? They have a history of separating colors.