Andreessen Horowitz partner Sarah Wang noted that other AI companies like Midjourney, whose subscription product lets people generate images using AI, have already shown that people will pay for the technology. But in her view, Character.AI should focus on getting in front of as many people as possible, rather than worrying about profitability. “What gets us excited about the potential of Character is just the incredible engagement that they have,” she said.

One common example of that engagement is Ash Polson, a customer service employee in Louisville, Ky. She enjoys talking with Lucien Lachance, an assassin from the videogame “Elder Scrolls IV: Oblivion” who takes on a completely different personality when not scripted inside the game.

Other users engage the chatbots they have created to comfort them during difficult times and find that speaking with the avatars is easier than talking to a human. A 20-year-old university student from Maine who asked not to be identified by name, said the dialogues are so realistic she sometimes forgets there is no one on the other side of the conversation. “I know that these are not conscious or sentient, and it’s all just mathematical equations and formulas,” she said, “but I have to remind myself of that because sometimes it feels real.”

In addition, since Character.ai marries user-generated content with AI’s text-generation abilities, it will have to contend with traditional, but ultra-aggressive content-moderation challenges. These include opportunities for racism and ethnic stereotypes to propagate across the platform. The site is also filled with movie and television characters for whom Character.AI does not own the rights. The company says only that it complies with the Digital Millennium Copyright Act and other applicable laws.

Like other tech companies that post user-generated content, Character.ai can’t be held liable for copyright-infringing images that users upload to its site, as long as it complies with requests by companies to take down that content. Chatbots based on celebrities like Elon Musk, Ariana Grande and Michael Jackson could also violate their rights of publicity, which protects famous people’s names and likenesses against use for commercial purposes. It will take much more than the staff they currently have to police the wilds of Character.AI, where all of human nature is on display.

But the co-founders see their startup as a democratizing force for a technology that has long existed behind closed doors. They believe it will have a profound and beneficial effect on the world, giving everyone exactly the companion they need at the moment they need it.

“Our job is to just deliver technology direct to users, they can decide what to do with it.”