Board Thread:Naruto Discussions/@comment-4271790-20141023105023/@comment-1629132-20141028225504

Blaezej wrote: NeedleJizo wrote: Icha Icha Sharingan, anyone? Huh?

They're referring to the adult erotic novels written by Jiraiya (the Icha Icha series) that characters such as Kakashi have been seen reading.