Brokenblue, I join the others who posted in this thread in welcoming you to TMF. This is an awesome place. I hope you enjoy it here.
Now, to answer your question. As someone who has what I like to call the dual "interest", of tickling, and female feet, I was into feet even before tickling. For me, I recall just deriving enjoyment from looking at female feet, from my age of reason. I used to love to see the pretty pedicured toes, or the soft soles, of a woman's feet, the way the foot and toes were shaped, and such. It wasn't until several years ago that I even realized the eroticism of the ticklish female foot, and that tickling really took over as an enjoyment. Now, I can look at a female foot, and not only direct my attention to it by how the female foot looks, but also, for myself, wondering how ticklish a particular female foot that I am looking at might be.
This is a very interesting topic you started. Iam sure you will get many replies. Have fun on the forum.
Mitch
P'S. I should add that Iam not at all "grossed out" by worshipping female feet. I love to do that as well, and again, was into that with my ex girlfriend, long before I even enjoyed tickling, or found tickling to be an "interest" or "fetish" for me.