Tummie fetish? iin

I have recently noticed that I think I have a fetish for girls' stomachs, not anything necessarily sexual, but seeing them and feeling them. I noticed this when I started to b become extremely attracted to certain kinds of girls... Mainly skinny ones.. And whenever I see their stomachs... It turns me on, sometimes even more than seeing pictures of them nude.. I have asked some of my friends, both guys and girls, and only one of them said that they have the same feelings. She is curious if she is bisexual or not and likes both girls and guys stomachs. I only like girls', but was wondering... IIN?