Chaco is a Japanese author known for her cell phone novel (keitai shōsetsu) The Gift from Heaven, originally posted on the website Mahō no i-Rando where readers ranked it number one out of over a million keitai novels on the site. It was subsequently published in print by Starts in 2005, becoming a best-seller. Like most successful keitai novelists, she published under a pseudonym, and her true identity remains unknown.