Male teacher, why is he hugging me?

I'm a 18-year-old female student from Sweden and my male teacher, 55, (married and has two adopted children) are hugging me every time I see him alone in his room when the door is closed. If the door is open or if I talk to him in the corridor he does not hug me, just smile at me a lot and intensely. Two times he has also touched me a bit over my hip as a respond to when I took my hand on his shoulder. This was shortly after a hug. We talk a lot and has a great contact and the same interests (history) and I also help him a bit at work. The last 6 weeks we have talked around 2-3 times per week alone in his room with the door closed, often around 1 h. Once, about 3-4 weeks ago, he also said I was his soulmate. Why does he say so? He only said it once though. Furthermore, he often refer to me as his best student ever etc. And as I said, he always get up from his chair and hugs me when I am about to leave after we have talked, and of course I answer. Actually I like it. Is it normal? Is he attracted to me and has sexual feelings towards me, or is it more like paternal feelings and a way to be friendly? Also: how do you think he would react if I kissed him on the check after a hug, maybe after the Christmas holidays? Kissed me on my lips? Be upset? Nothing?