A cold-blooded psychopathic killer seeks satisfaction from knowing the victim saw his death coming. They often sacrifice the advantage of surprise to make sure the victim sees the revenge is at hand. They also keep souvenirs, pose their victims, etc.
I suggest this explains why Jodi took pictures of TA in the shower. I believe (MOO naturally) that he was stabbed in the heart while his arms were duct taped together (tape going around his back sticky side down) and she was sitting on top of him. Thus disabled, she could untape him and let him shower while she got dressed, got her camera ready, etc. He thought she was gone so he wasn't running anywhere. He didn't realize he was critically wounded - you can see him putting pressure on the chest wound while in the shower. He sits down in the shower because he is feeling lightheaded.
When Jody returns, she has the gun and the camera. She is ready to take her photographic record of his murder so she will have pictures of him seeing his revenge coming, begging for mercy, dying cleanly from the gunshot wound. She also doesn't realize the heart stab was not immediately fatal. She opens the shower door, he sees her and is surprised and terrified at the same time- hence the "what the hell" look on his face. She shoots, he experiences a huge jolt of adrenaline and lunges at her--she tries to shoot again, the gun jams and she runs back to the bedroom to get the knife.
TA had fallen to the ground but pulls himself up to the sink coughing and choking with a bullet in his cheek. He is in great pain and is screaming for help. She returns with the knife and tries to finish him off and her fury increases as she is fearful someone will hear. The battle goes down the hall, she slits his throat there and then drags him back to the bathroom, trying to reclaim the scene as it should have been, as she imagined it would be in those hours driving to Mesa.
He spoiled it and made a huge mess when it was supposed to be so simple. Him thwarting her plans yet again explains the rage escalation that lead to the vicious almost superhuman strength she had to almost decapitate a man and then drag his body.
I think she forgot all about the camera in her wild antics afterwards where she ran around bundling up sheets to throw in the washer. I think she took the pillow to use sleeping in the car, used the pillowcase to stuff her bloody clothes in, and left the house in a rush.
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