A thing that is new, unused, untouched, uncorrupted, beautiful, and clean; retaining no dirt or scum. Remaining in a pure state. Normally used for either one's own new belonging, or someone else's belonging whether theirs is used or not. Much emphasis is put on the word 'pristine' as it is spoken.
...Holy shit, that dude's Honda Rebel is pristine.
When a situation becomes violent, dangerous or risky - for example, walking into a pub or bar and the atmosphere is already hostile, and all it will take is one wrong word, one spilled drink or a single push or shove before a fight breaks out.
Can also be used by a single person when they've been pushed to breaking point as a warning to others.
(In a pub or bar) "Let's get out of here, it's going to get pristine in a minute"
(Person in a bad mood) "I've been up since five this morning, I've had a really bad day and it's going to get pristine in a minute..."