In January 2023, Akio Kodaira, while pursuing his Ph.D. at UC Berkeley, embarked on a groundbreaking venture by launching an AI Virtual YouTuber (VTuber) named Shizuku on YouTube. Shizuku, equipped to converse with audiences in both Japanese and English, sing, and interact in real time using a Live2D avatar, quickly captured the attention of viewers. Over the course of numerous live streams, Akio cultivated a community of thousands who engaged with this AI character that exuded a remarkable sense of presence. At the time, many perceived it as a passion project; however, it soon became evident that it laid the groundwork for an ambitious future.
The significance of this endeavor can be traced back to Akio’s academic contributions. He served as the lead author on the noteworthy paper StreamDiffusion, which set a new standard in real-time image generation with capabilities exceeding 90 frames per second—an impressive feat for live video applications. This open-source project has garnered an impressive following on GitHub, with over 10,000 stars, and was showcased at ICCV 2025.
The vision behind Shizuku has now evolved into Shizuku AI, a company dedicated to creating an AI lab in Japan that focuses on the development of AI companions and characters. This initiative seeks to blend cutting-edge research with the beloved stylings of Japanese character design. The initial goal is to enhance Shizuku’s functionality through advancements in multilingual voice synthesis, enriched conversational AI, and expanding her presence across several platforms such as Discord, YouTube, and X.
A significant challenge in the realm of AI companions lies in the scarcity of data required to foster engaging and proactive conversations, often resulting in monotonous interactions. Akio aims to address this by deploying Shizuku across diverse platforms, enabling a community-centered approach to her evolution. This feedback loop is critical for developing a more engaging AI that feels responsive and alive.
Akio’s strategy emphasizes the necessity of community involvement in character development, positing that characters deserving of affection cannot be crafted in isolation. They must develop through genuine relationships with real people, echoing the progression seen in iconic figures from Japanese media. His background includes experience at Meta, where he focused on real-time video generation, followed by a research role at Luma AI. This unique blend of technical prowess, cultural insight, and practical experience equips him with the tools needed to create a captivating AI character.
Raised in Japan, Akio was influenced by narratives featuring artificial life, such as Doraemon and Mega Man Battle Network, alongside numerous anime in which AI companions play roles beyond mere tools, embodying friendship and partnership. The global success of Hatsune Miku cemented his belief that these fictional relationships could eventually become a reality through AI.
The enthusiasm surrounding Shizuku AI is palpable, especially among investors who recognize the potential for AI agents that resonate with people on a personal level. Akio’s long-standing commitment to this vision has positioned him as a pioneer in the sector, generating excitement about the future of AI companions.
As Shizuku AI continues to grow, the company is actively seeking talent both in Japan and internationally, appealing to those passionate about the fields of AI companionship, character design, and the convergence of technology and entertainment.
