'sinister aura' is a valid and commonly used phrase in written English.
You can use it to describe a situation, environment, or person that feels foreboding, dark, or creepy. For example, "The old abandoned house had a sinister aura that made me feel uneasy."
On the choking, gridlocked streets of Tehran, motorcycles are taking on an increasingly sinister aura.
There was a smoke machine and really dark lighting, which lent a sinister aura to a collection that otherwise had a lot of fancy jacquard pants in it.
But no date, especially in the northeast, is thought to have a more sinister aura than Aug. 24, St. Bartholomew's Day.
The store's alluringly sinister aura is, in fact, a major selling point, a mood that has been faithfully replicated in most of the company's 70-plus shops around the world.
The slightly sinister aura seems appropriate, given that Bacon's estate has been involved in lawsuits charging art world skulduggery, and leads one to wonder if Bacon really did leave his studio just like this.
At Altamont, however, the dance moves take on a sinister aura, since the dancers seem to be getting off on no-one but themselves.
If you say "Don't be taken in by my dexterity, despite the spurious rightness, I'm a suppressed sinister" auras swirl.
With this project, Ackermann and Gobert sought to illustrate the still-sinister aura that hangs around these disgraced relics.
In this glum milieu, divorced alcoholic Rachel Watson gets a bottle of chenin blanc from a Whistlestop to take the edge off her return journey – and the bundle of rags she glimpses from the window takes on an aura of sinister abjection and threat (actually, a not unfamiliar feeling to anyone who's ever rolled on tracks that fall under Network Rail's cheerless ambit).
That of course avoids the uncanny valley pitfall that designers of humanoid robots still run into — whereby the disconnect between how simultaneously similar and dissimilar a human-esque creation looks to a (genuine) human eye lends it a sinister or otherwise unpleasant aura.
Ever since the opening of Tutankhamun's tomb, the aura of the sinister that supposedly did for Lord Carnarvon has been counterpointed by a distinctly aureate glamour.
