Snaptwat
The Snapchat user with the insatiable urge to take a picture of their genitals and distribute it generously to a number of unsuspecting victims in their contact list.

Typically, the Snaptwat will set the timer to two seconds, effectively eliminating the possibility of the recipient taking a screenshot and using it for the purposes of blackmail at a later date.
"I just received a Snapchat from my grandad".

"What is it of?".

"It's just another picture of his wrinkly, old bollocks"

"Your grandad is such a Snaptwat!"