I don't know exactly how long I spent masturbating yesterday afternoon or last night (that's poor behaviour on my part - I'm sorry Master). But I do know that each time was longer than one hour.
The afternoon session was spent masturbating on webcam for my Master, while the night session was spent having phone sex with Him.
I came once in the afternoon session, and twice during the night session.
(I have been reprimanded by my Master previously and have been instructed that I must state the duration of my masturbation sessions, so that you all know just how much I love having my hands between my legs, trying to get myself off. I am positive that because I was careless and failed to note the duration of both these sessions, that I will be punished accordingly and as He sees fit, when we're next together).