I've got a couple of inputs on this. Firstly, a few years ago I was on my lunch break talking to a female colleague who had just finished her own shift. I had bought a sandwich and a cream choux bun earlier that day so I was just about to start eating the sandwich. My colleague looked at the bun and said it looked nice so I said she could have it. We had joked about foam in faces a couple of days earlier. She picked up the bun and removed the top pastry off it to have the cream showing that is normally inside the bun. She walked over to the staff room door and closed whilst saying, we don't want anyone walking in because this is going in your face. My heart skipped a beat but thought it wouldn't happen and it was all a joke so I carried on with eating my sandwich. I took one bite and she walked over to me. She suddenly put the bun in my face and rubbed it all around covering my face. She just laughed and i just carried on eating my sandwich with cream still over my face as I was hungry but very happy. She asked if I was ok and said yes that's fine. She then continued to put the bun and all the cream on to me including my ears whilst i finished my sandwich. Basically I spent the majority of my lunch break covered in cream. She had to leave then she rung me on her way home to ask if I was still sat there covered in cream which I wasn't. This was the start of a series of little tit for tat cream pie encounters with this colleague which we're very enjoyable and fun. Nothing ever came of it just a lot of fun between friends. The best one was where she came up to me on an early shift and she made a shaving cream pie on paper plate and smeared it around my face then into my hair saying that my hair gel would allow me to restyle my hair after I got clean as it was still fresh on.
The record time in a full session is about 4 hours due to multiple pieings and fun in between the pieings with then girlfriend and now wife.