I used to do this even before I started ejaculating. But I'd rub my penis side to side instead of thrusting. In my teens I'd use a mirror to see the sperm come out.
I used to do this dressing in my moms slips, panties, and skirts. What a fucking rush. Jerking off was my alternate. Id set up mirrors and watch myself doing this all sissied up. I use to do it in front of guys in school, they were amazed. Also did it with guys fucking my ass. Now that was a rush!