MTFU. Stand by the door and do your pissing from there. Splashback no problem. 🙂

@ phil: There’s absolutely no chance that could go wrong….!

I have two things to say on this

Masturbating in the workplace is a serious offence

Even if it is in your lunch break in a cubicle with the door locked?

What you need to do, is wait until he is at the sink, run up beside him and piss in the sink next to him. The curve of the sink will cause the piss to naturally curl, leap out of the edge and soak him right on his crotch.