When a man masterbates and jizzes into a cup before locking it away, so he can therefore keep track of his ejaculation amount, over time. The man may then decide to show a potential girlfriend his produce from his Proudlock to show his capability to ejactulate large or small amounts.
Hey dude, you can ejaculate very much,

Man, yes i can ill show you my Proudlock
by William Giggs February 6, 2011
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