Silent Ninja 

When a guy is having sex in the doggy-style position and spits in her anus and slowly and silently slides his fingers, usually his thumb or middle finger, into his woman's anus for better stimulus and for his own self-enjoyment of the moment, gently stroking it in and out, with the hopes that she doesn't mind or won't say anything! That's a silent ninja!

On the bad note: It could also be reversed too. A wicked girl can give her boyfriend a silent ninja too! And he might end up liking it!!!!

Last night I gave my girl friend a silent ninja and she didn't mind. I guess she likes it in the ass after all?

Silent Ninja by Attila the Milf Hunter July 30, 2010

silent ninja 

A fart that goes by silently, and everyone but you can smell it.

jon let off a silent ninja.

silent ninja by El Skeeto April 11, 2007

Silent 4am Ninja 

is a term used to define the person who wakes up hungry at dawn, he tries his best not to make any noise to wake up his relatives, but most of the time he fails miserably

You're mom hate you for being a Silent 4am Ninja

Silent 4am Ninja by MinecraftFan123 October 9, 2021

silentninjakilla 

an idiotic kid browsing the internet.

you're such a silentninjakilla!

silentninjakilla by koolaid duud May 14, 2018