The unhallowed notion one has to think about though, it probably already is.
From the economist.com
I saw the pale student of unhallowed arts kneeling beside the thing he had put together.
From the en.wikipedia.org
It's Halloween, and I'm on my way to Toronto, where I'll be spending a most unhallowed evening giving a talk.
From the scienceblogs.com
Places that Tibetan Buddhists revere as the dwelling places of deities nurture more types of plant species than nearby unhallowed ground.
From the newscientist.com
Two decades later and heads of leading schools know they would be hung from the nearest lamppost and their entrails scattered on unhallowed ground if that figure wasn't at least 60 per cent.
From the telegraph.co.uk
More examples
Unholy: not hallowed or consecrated
Unhallowed is the debut album by American melodic death metal band The Black Dahlia Murder. It was released through Metal Blade Records on June 17, 2003.