A yellow wank is necassary when a regular wank just isn't going to be enough and usually involves loading up the dirtiest Asian porn the internet has to offer and wanking yourself into a coma.

Abuse of the yellow wank is not advised and it should only be used as a monthly treat. Binge drinking is attributed as the most probable cause of the 'yellow wank' urge.
James: "I cannot wait to get home guys, then it's straight upstairs for a reet session of slap and tickle"

Isaac: "To be honest James I think the only thing that's gonna calm these urges is a yellow wank"
by jMiR January 2, 2011
Get the Yellow Wank mug.