This is a fun use of a We Vibe. I don't know if any of you have come across the We Vibe, but it's a fantastic bit of kit.
It's designed for couples, but has so many more uses, and being water-proof it can be used for a bit of fun in the shower.
I like to get the shower nice and hot, then cover my whole body in a thick layer of foam. Starting the vibe on it's lowest setting, I rub the larger end over my balls whilst slowly stroking my soapy shaft. As I get harder and the pre-cum starts to leak from the tip, I push the smaller end between my buttocks and let it rest on my anus. Feeling the vibrations soaking into my ass as I squeeze my cock is just a fantastic sensation.
I sometimes (but not always) slip the small end of the vibe into my ass and feel my whole insides light up with sensation. With a little careful positioning, I can hold the larger end against my perineum, stimulating my ass and balls as I pull on my hard wet penis. Finally, when I have teased myself for long enough, I set the vibe to the it's wave setting and then pulling my foreskin back tightly, I sandwich the sensitive head between the 2 ends of the vibe, and start to squeeze in time with the waves soaking into my skin. I take the shower head off and angle the jet at the underside of my balls and turn the vibe to its highest setting.
The electricity that goes through my system as the orgasm hits is so intense that I sometimes lose my balance and have to drop the shower so I can steady myself. As I come down from my orgasm, I watch the ropes of my cum slide down the glass wall of the shower. I then turn the shower down and rinse myself off, paying close attention to my sensitive head and balls. I masturbate this way at least once a week, and sometimes do it as a bit of a show when my wife is in the bath (which looks directly into the glass wall of the shower). She loves it when I come this way and will either play along as she watches, or when I'm done she'll drag me into the bedroom for any number of naughty things. Long and short, I can highly recommend this technique and I love doing it.