Anyone know of a strap-on that massages the wearer?

My girlfriend and I are looking into finding on. I like the idea of wearing a strap-on and having sex with her, but the harness kind of makes me feel weird and it's not always comfortable. I've heard of a toy that's pretty much like a strap-on but there's suction that would massage my private parts while I'm wearing it. Anyone know what I'm talking about and/or where I can find something like it?