Ninja Wank Edit Meaning

1.

verb: to masterbate in the presence of others without their knowledge, typically in a bedroom situation. A skill used by frustrated individuals who must share sleeping arrangments with another who wants nothing to do with them sexually but must still fulfill their sexual needs.

She said she had a headache, so I waited until she went to sleep and ninja wanked.

Dude, sharing a room with my brother sucks. He's always ninja wanking when he thinks I'm asleep. It's freakin' nasty!