BunCho: AI Supported Story Co-Creation via Unsupervised Multitask Learning to Increase Writers’ Creativity in Japanese

Co-creation with artificial intelligence (AI) is an upcoming trend. However, less attention has been given to the construction of systems for Japanese novelists. In this study, we built “BunCho”, an AI supported story co-creation system in Japanese. BunCho’s AI is GPT-2 (an unsupervised multitask language model) trained using a large-scale dataset of Japanese web texts and novels. With BunCho, users can generate titles and synopses from keywords. Furthermore, we propose an interactive story co-creation AI system as a tabletop role-playing game. According to summative studies of writers (N=16) and readers (N=32), 69% writers enjoyed writing synopses with BunCho more than by themselves, and at least one of five common metrics were improved at objective evaluation, including creativity. In addition, 63% writers indicated that BunCho broadened their stories. BunCho showed paths to assist Japanese novelists in creating high-level and creative writing.