Toboso Yana posted an entry in her blog about illegal manga and anime downloaders. She often receives letters from fans writing that "I borrowed scanned manga in ROMs from my friend wwww (i.e. lol)" "I've watched Kuroshitsuji on foreign video sharing sites!". She insisted that such acts are definitely criminal and stated that sending such letters amounts to an insult by saying "I love Kuroshitsuji, but I wanna let the creators starve to death."
"Quoting from Fullmetal Alchemist, it's against the rule of Equivalent Exchange to spend no money on anime making excuse that you cannot afford DVD or Blu-ray. ... Paying a little for rental DVDs or character goods will greatly help the anime and manga industry. Otherwise, we cannot continue creations."

note: Watching illegally uploaded anime on streaming sites is legal in Japan. Deliberate direct downloading is illegal.

Mangaka TAGRO responded to Toboso's post that it's encouraging to see such a distinguished creator has spoken out about the issue. Illustrator Shimada Humikane said illegal uploaders won't listen to her, but he wants the fans to refrain from talking openly about watching pirated materials.

Sources: Yana's blog, TAGRO's tweet, Shimada's tweet