MAPPY is a large, rectangular adbot that has map data stored within it. Your first brush with this device will be in the Pleasure Port. As you don't have to worry about claiming the map data just yet, I would instead suggest two things: destroy this walking "You are here" notice, and then immediately quit to the main menu. Continue on from this point and then you can claim the map data and the trophy with the same room/unit.
To be fair, this is the earliest you can get the trophy. You might be going back and forth in some areas where you will end up encountering other MAPPY units, but the map data is only available once; as such, weigh the possibility of killing them first and then returning at a later time to download the map data.