As I fixed your collar, my fingertips barely grazed your pulse but it was just enough to feel the blood rushing underneath your skin. Pulse quickened: check. I only had to make brief eye contact, look up and down again, to see the expansion of your pupils. Eye dilation: check. Don't think that I didn't hear or feel the breath you didn't realize you were holding in. Shortness of breath: check. Hmm. Interesting.