I've really enjoyed doing this lately. I'll turn the shower on warm, then I'll lay down in the tub so the water is coming down on my cock. then, I'll use my body wash to lube up my asshole and I'll use my finger to fuck myself to get warmed up. Then I lube up my vibrating razor and shove the head as far as I can into my asshole. The vibration feels great and when its as far as it can go into my asshole, I'll start jerking off until I cum.
It's amazing.