I find his facial expression particularly interesting, it is as if he is expecting her to be proud, proud that he has forever and permanently given up all of himself for her sake, and now she is expected to do the same. There is no more worming herself out of this anymore.

In Shots and Such, the reason he gives for not killing Julia is simply that she would never appreciate it anyway. But in Burial? She HAS shown appreciation for him, and it is a sensation he has become addicted to and wants more of it, what better way than sever his ties to her?

An aspect of Burial (especially Questionable) is Andrew willingly shedding all of his mask, the one that pretends to care and to be a good person. Its because he finally has everything he wants in Ashley, appreciation, so he no longer needs to keep an idea that he can 'get away'

Theory time: Lots of people see this Burial Teaser and (understandably) assume it is probably regarding Six Eyes/The Cult What if this is instead regarding JULIA, serving her head on a silver platter, offering it and by extension, all of himself for his beloved Ashley's comfort?