When you see the text above the heads of NPCs in a Hangout Spot, they are having a conversation. If you wait and listen to the whole thing – which doesn't last long – you may receive a keyword, but neither can you.
These keywords can be something like a good coffee, or a gift, or something quite random. We believe they are used to start secondary suitcases when they become available. This is the sole purpose of Hangout Spots.
We got a keyword for “noise” by listening to a conversation passing by. This led us to investigate where the noise was coming from, which ended up being a secondary case. Even though the keywords you get are useless when you get them, they will eventually be used as you progress through the game.
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For those who don't know what a Hangout Spot is. As you explore both cities in Lost Judgment, there are a ton of greenish triangular speech icons on the map. If you press L1/LB, the display icon caption will appear, called Hangout Spots.
If you go to one, there's nothing interesting there, just people talking, and who has time to listen to that when you're trying to solve a murder case. But these Hangout Spots have a purpose, but the game doesn't seem to explain what.
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