A person who wanks or masturbates. Also used as a common insult. It can be used literally if someone does indeed wank or laterally for someone who you just hate or has done something bad to you.

A pretty boy who always takes Instagram selfies with his shirt off.

An insult. Some one who beats his own meat, chokes his own chicken, or spanks his own monkey.
See also: jag-off

you

Someone who wanks

Someone who is very annoying,

The middle of the three size classifications of the human penis, the sizes, in order, going like this:
-Wonker
-Wanker
-Winker