Ninja Cum: (1) The act of cumming inside of somebody without them ever knowing. (2) Also, the act of cumming on an unsuspecting victim without them knowing.
(1) Girl: Well that was fun, sorry you didn't finish Guy: I liked it ... one week later. Guy to Friend: I totally ninja came (past tense of ninja cum)
(2) Person 1: (time to ninja cum) *jerk, jerk, jerk* Person 2: *yawn* Person 1: *SPPPLOOOOOOSSSSHHHHH* Person 2: *yawn* Person 1: *silent zip* well, see you later. Person 2: bye
Ninja Cum (verb) is the wholesome act opon which a man sneaks behinde a unknowing victim (usually female) to simulate the characteristics of a ninja. Than proceeds to ejaculate over the unknowing victim,
then vanish to avoid atention of the victim to the next target.
Example
Guy1: "Dude, you should totally ninja cum that chick over there!"
Guy2: **Sneaks to unknowing victim then ejaculates all over her then get away without being noticed**
Her: "Like OMG WTF, Who just cummed all over meeee!"
To ejaculate in such a quiet or subtle way that your partner either barely noticed or did not notice at all.
girl: why did you stop?
guy: rolls off
girl: WTF. Did you cum?
guy: yeah
girl: I couldn't tell. That was quiet.
guy: Like a ninja. I guess i ninjaculated.
It is said of the situation where a person has the bad luck to make contact with his testicles against an undefined surface or object, intentioned or not.
Given the nature of the word, it is more appropriate to design cases where the interaction is made with a moving object, for example, a ball.
Although it is extremely painful for the victim, it tends to be considerably funny to people who witness it.
Today in the baseball game the pitcher took a nutshot; the baseball hit him in the nuts.
Man, I just watched the funniest nutshot video ever.