A seat in most any car can "twist" like this if someone very heavy gets in the seat, especially if they "flop" in and then wiggle around in the seat.

I have a cousin that lives out of town that was visiting last summer. He is a big guy (about 6'2 and 300 lbs - if I was guessing) and he plopped down in the seat of my dads car and popped something in the seat and it was all leaning back and was making odd noises. My dad had to take it apart and repair it. That is one reason I keep ALL of my cars locked when they arrive. I do not want anyone damaging my seats.

I know a lady at work that has a daughter that weighs 600 lbs. She drives her car (92' Buick) sometimes and the seat is severely warped. I am not saying this to be mean or making fun, as I am very fond of that lady, but its true. Seats are designed to take only so much weight & pressure.

I used to have an 84' Accord years ago and its seat was also twisted to the back on one side. It was rather annoying.