When you poop directly into a girl's butthole and then use it as lube for anal sex

The safeguarding of Earth and other worlds from biological cross-contamination (i.e. billionaires with too much time on their hands).

Also known as “planetary protection.” Planetary protection / quarantine “reflects both the unknown nature of the space environment and the desire of the scientific community to preserve the pristine nature of celestial bodies until they can be studied in detail.”

There are two types of interplanetary contamination. Forward contamination is the transfer of viable organisms from Earth to another celestial body. Back contamination is the transfer of extraterrestrial organisms, if such exist, back to the Earth's biosphere.

To be such a rephrehensible person, that you think it is really funny to (whilst also getting a great amount of personal pleasure from) putting your fingers into a girls mouth, without asking for permission.