It's and interesting premise

Rating: 4/10 (18 December 2019)

It Follows has a high degree of original content in its set up: the originating premise is stark and bold. Imo however that is by far and away the best feature of this horror film.
Even this though has the unfortunate defect of inviting speculation as to the immediate metaphorical meaning of the 'sexually transmitted misfortune'.
There remains the decided possibility that it's just a good way of making the mechanics of a slasher teen horror film unfold as usual; and we are dealing with a neat and direct take on a writers crafting of cause and effect upon their story and their characters.
Another possibility is that it's a direct filmmakers reference to the well known trope of this sub-genre to use youngsters getting frisky as a means of imperilling them at the hands of a monster that has used their 'distracted' state to get into an attack position!!
A trope which is often over-analysed by film critics and fans as having moralistic rather than mechanical meanings.
At times, particularly in the initial encounters with 'It' a good eerie atmosphere is generated; and this lasts for a fair while into 'It Follows'.
Sadly as the plot proceeds most of this good work meanders and becomes formulaic with unremarkable straight forward exploitative shocks and 'nasties'.
This left me less and less impressed and less and less sympathetic to the protagonists and to the film as a whole.
My final rating is a strong 4/10.....with some recommendations but overall I'm not going to say that I enjoyed 'It Follows' any more than that; by the end I found it to be simply serviceable slasher horror