Not sure i'd say "horrid"... it looks like a parallel LB squat.
Some thoughts:
- Knees are coming too far forward. Sit back more so your knees don't come so far forward. This will also get you a bit more depth
- push your knees out and keep them there. The thing that looks most strange about your squat is that there's a lot of corrective "motion"
- also your feet seem to be turned out too much ( don't know if your heels are too close can't tell from these angles). This might be causing some lack of stability which is causing that knee motion.
curious to see what others here have to say. Also lowering the camera about 2 feet would give a better video.