Is it common for guys to have a foot and armpit fetish?

My boyfriend loves to smell my underarms and one day he lifted my arms and just smelled them up and down and kissed and licked them and it turned me on so much, he was turned on too. I always let him do it, I don't mind it and I actually like it. He also likes to touch and look at my feet and even rub them on his face and hold them. Again I love it, it weirdly turns me on I think because it's so unusual but also the fact that he literally loves every part of me.