12. Splay your knees out to the side: You’re flirtatious
Assuming you don’t take this position for pure comfort, stacking your knees to one side, and propping yourself up, on one hand, is thought to be flirtatious. For women, it makes their upper body more available to the other person.

13. Lean backward on your palms: Judgemental
This sitting position indicates that you are judgmental. Leaning back lets you assess a situation without taking action.

One’s comfort is definitely a major thing here but the same sitting position do tell a lot about your personality.