A legendary number

69 is the sex number. 69% of the world thinks dirty thoughts.

The number that: in between 68 and 70

A great thing ruined by a period.

This is a common joke. A 69 is were two people give each other oral sex at the same time. When a woman is on her period this is impossible due to all the blood. This is a joke were 69 is the great thing, and the actual period is making it a 6.9, while it's also true that a woman's period ruins a 69.

The magic spell that harry ingeniously used during the "sidemen go back to school" video.

haha, nice one

This is what girls and boys do or maybe same gender even.