The most popular instance of this that has actually been "documented," did not actually occur in a house at all, but at a hotel in Jakarta, Indonesia. Damian Leong, an Indonesian man, claims in a Facebook post uploaded on the morning of June 11, that he and his wife had seen The Conjuring 2 together before returning to their hotel and immediately fallen asleep on the bed.
In the middle of the night, Damian's story goes, his wife awoke him and asked if he was playing a prank on her. When Damian asked her what she was talking about, she told him that she had awoken a few minutes earlier and gone into the bathroom to brush her teeth, only to find a cross (one of the symbols used by the demon in The Conjuring 2) drawn on the mirror. Damian went to check the cross himself and verified it was freshly drawn.
A bit freaked out, Damian and his wife asked the hotel staff if they could switch rooms, and the staff quickly obliged.
When the couple went back to the "haunted" room the next morning to retrieve their belongings, they found that the cross had been erased.
There are many other claims of post-Conjuring 2 viewing hauntings going around the internet, but these two, along with the story about the disappearing Indian corpse, have achieved the most popularity. And because of them, a sort of urban legend has begun to surface that The Conjuring 2 is a vessel for demonic energy.
Many sources discussing the buzz point out that the first Conjuring movie complained about just these kind of supernatural occurrences happening after they watched it, and Universal actually hired priests to bless viewers after screenings in order to deter the events.
Although a priest blessed The Conjuring 2's set before filming started, the same priests were not made available at the movie's screenings -- could that be to blame for all these extraordinary happenings?