The spiral represents the spiraling motion of the bottomless pit. It's around his head symbolizing how the bottomless pit is in the head.
Bottomless pit swirl in forehead.
In this one it seems he's coming out of the pit.
Bottomless pit swirl on flask. Leonardo DiCaprio is under dirt in a grave type setting which he rises from symbolizing the beast who ascends from the pit.
Symbolic for fornicating with satan and fallen angels opening the bottomless pit and taking the mark of the beast.