90us, Inc.

Company

Company Name

90us, Inc.

Founder

Hayato Hoshikawa

Location

San Francisco, CA

Incorporated

January 29, 2026 (Delaware)

Product

PopTalk: Learn Japanese with AI Characters


The number of Japanese language learners is growing at a CAGR of 15%, driven largely by anime, manga, and J-Pop culture. PopTalk is building an app that lets users practice Japanese through conversations with AI characters. Learn real Japanese through conversations with your favorite characters. We are creating a new language learning experience powered by "Entertainment × AI."

Strength

Core Technology: Generative AI / LLM Optimization for Consumer Services


We develop proprietary tuning technology specialized for entertainment experiences, not generic models.

 - Character Tuning: Building LLM models that maintain character personality, tone, and worldview throughout dialogue
 - Japanese TTS: Tuning technology that reproduces natural, emotionally expressive Japanese speech using AI voice synthesis