I've loved being tickled since I was little. I had fantasies about it starting at age five, and the feelings of anticipation and submission and 'helplessness' I had as a kid are just like the feelings of arousal as an adult. I'm ticklish most everywhere, but especially on my feet. I can orgasm from having a particular spot on my feet stimulated in a specific type of tickle. Even without orgasm, having a lover tickle me or even 'threaten' to do so gets me aroused, every time. It's the most reliable form of foreplay for me, and the embarrassment aspect enhances my arousal. I read that the part of the brain which registers genital sensation is right next to the part of the brain which registers sensation on the soles of the feet. My theory is that some brains get those wires crossed, leading to arousal/orgasm. Regardless of why or how it works, I'm so lucky to have such an easy way to get aroused and orgasm. It's a wonderful secret to share with my lover.