Can condoms be used for masturbation? Or is that a waste?

If one masturbates but does not get involved in any other sexual activities, is that person considered to be sexually active?

I know this sounds gross, but sometimes when I get turned on, I like to rub my "vaginal area" on a stuffed dog. After it, I feel good, but a few minutes later, some discharge comes out on my underwear. What's going on, and is this safe?