Hi Product Hunt 👋 We built TheirSide around a simple idea: a character conversation may start 1:1, but creative scenes often need more voices. We wanted one private place where a user could begin with a single fictional AI character, expand into a group room, and continue with a shared story setup. The hard part was not just adding more characters—it was making multi-character turns feel coherent. We moved away from fixed speaker slots toward flow-based turn selection, then repeatedly tested our Mio + Kai guest room and published both the observed results and the limits. Today TheirSide runs in the browser, includes a no-sign-in demo, supports custom fictional characters and group rooms with up to four AI characters, and has a Free plan. We’d love feedback: • Does moving from 1:1 chat to a group room feel natural? • Do characters react clearly enough to the shared conversation? • What kind of story setup would you try first? Thanks for checking it out.

TheirSide

Chat with one AI character—or bring four into one room

Chat with one AI character—or bring four into one room