If so then yes, you can leak
milk during foreplay. The hormone that releases all the
milk is called oxytocin and it's the same hormone that's released when you climax and have an orgasm.
If you aren't breastfeeding and you are leaking milk then I would suggest you go to the doctor and get a checkup. You may have a benign tumor on your pituitary that's making you produce milk when you shouldn't.