Private from the public is only the first layer
Most companion products use private to mean that your room is not visible to followers, search engines, or a public community. That is meaningful: it removes an audience and reduces accidental social exposure. It is not the same as a message being readable only by you and the fictional character.
The character is software. A hosted service must receive your text and run it through systems that produce a reply. Privacy evaluation begins by separating public visibility from backend processing.
Map every system that touches the message
The path often includes your browser, the companion product server, a database for signed-in history, logs used for reliability or abuse prevention, and a third-party model provider. Analytics may also record page visits or product events without receiving the full conversation.
Look for those categories in the Privacy Policy. A product does not need to publish infrastructure secrets, but it should explain the purpose of collection, the kind of service provider involved, and how long important data is kept.
Do not infer encryption from visual design
A lock icon, dark room, or secure badge does not establish end-to-end encryption. Transport encryption protects data while it moves over HTTPS. End-to-end encryption is a stronger architecture in which the service itself cannot read message content. If a product offers it, the claim should be explicit and documented.
Most cloud AI services need readable text on a server or model system to generate a response. Treat vague encryption language carefully and ask what is protected, from whom, and at which point in the path.
Guest mode and account history solve different problems
Guest access can reduce the amount of account information required for a trial. It may keep a draft in local or session storage and limit how long the conversation continues. It does not automatically stop the service or provider from processing messages sent during that trial.
An account makes continuity possible by saving rooms and associating them with a user. That can be the feature you want, but it changes the data picture. Check deletion controls before building a history you would later struggle to remove.
Share the minimum useful context
Replace names with roles, remove exact locations, round numbers, and leave out identifiers. Say my manager instead of a full name, a recent result instead of a medical record, or a financial decision instead of an account number. The companion can often help without the sensitive detail.
Never put passwords, authentication codes, payment credentials, government identifiers, confidential work data, or information about another person into a companion chat. When the stakes are medical, legal, financial, or urgent, move to a qualified human and an appropriate confidential channel.