
It may happen, for example, if you leave it in the underground, use a teleport and go fight on the Arena of the One during The Collar quest.
NOTE: If you leave the cat alone it may disappear. In most cases, it will be patiently waiting at the altar until you return, especially if it was just for a quick shopping and you were back in 15 minutes. If, however, you do use the altar, the cat won't be transported with you. It will be safer to simply walk it off, rather than tempting your fate with teleportation. Forget about the teleporting altars for a moment. The black cat doesn't like fast travel. Don't forget to heal it, as it's got low HP. The cat is vulnerable to environment and status effects! While it can run pretty fast, it sometimes happens to run across fire or poison. The cat is marked as a yellow dot on the map - keep an eye on it all the time!. You'll just have to talk to it again to have it "rejoin" your party. The cat will spawn close to you once you exit the location. Don't worry though - after the fight, simply leave the loot for a moment (you'll get back to pick it up in a moment), and head for the same exit the cat took. Underground Tunnel, where we encounter fire snails). Sometimes, the cat will run across the whole map to leave it through one of the location exits! This happens especially often in Fort Joy underground (e.g. The cat likes to vanish after combat! During a fight, the cat will usually hide several dozen meters away, and return to its "special person" after the battle. Since it isn't affected by turns like the rest of the party, it will move in real-time until its AI believes it's safe.
The cat will flee from combat, and turns will have nothing on it! This means that when a fight breaks out, the cat will try to find a safe hiding spot.
If you really have to talk to the guards, have the cat and it's "master" wait at a respectful distance. This means that you can separate the cat's keeper from the rest of the party to keep the cat safe from stray arrows.
The cat will stick to ONE of your party members, not your party as a whole. The guards here apparently hate cats, and may send an arrow out of pure spite, ending all of the cat's remaining lives. To keep the black furball alive, you'll have to remember about several important things: In other words, you simply have to bring it to The Hollow Marshes. Well, the OBJECTIVE of this mysterious quest is to escort the cat outside the Fort Joy stronghold. We have no control over its actions, and often it will vanishe or get killed before we even notice.
The charming black cat isn't the nicest traveling companion.