Citizen Sleeper

Short version: Complete Emphis's tasks (Drive "Get to Know Emphis").

Detailed version:

Find Emphis's stall by successfully completing at least two bars of the exploration wheel at the Bright Market compass icon. Go through a dialogue with Emphis (choices don't matter), he will give you free food. After that, food costs 15 Cryo (which fills 3 portions of your hunger meter).

Buy food from Emphis's stall 4 times to fill the Fungus Fan wheel. Go through another dialogue with Emphis. You'll then need to get 3 Girolle mushrooms. There are 3 ways to do this:

• Go to Mushroom Groves in the Greenway and get the positive outcome for action "Forage for Fungus". Getting a positive outcome results in getting a Girolle cap. (Neutral and negative outcomes do not provide a Girolle cap.)

• Grow them: see the solution below. You will probably not get 3 Girolle caps in your first harvest, so repeat collecting spores, germinating spores, and harvesting mushrooms until you have at least 3 Girolle caps.

• Steal them from Midline Freight Hub: one of the possible outcomes for stealing is getting 2 Girolle caps. However, another possible outcome is getting shipmind fragments, which I would recommend over Girolle caps. See the solution below for details on stealing from Midline Freight Hub, which states how to control the outcome of stealing.

Return to Emphis's stall after acquiring 3 Girolle mushrooms, give them to him, wait 3 cycles, and go through another dialogue with Emphis. (Note that during these 3 cycles, you will not be able to buy food from him, so know where you are going to get your energy: Overlook Bar, Min-Gi Express, Hypha Commune, Farm Stacks, or Sunbathe perk.)

After the dialogue, you will need to bring 2 Matsutake mushrooms to Emphis. The only way to obtain these is by growing them at the Aviary. After harvesting at least 2 matsutake mushrooms, return to Emphis's stall and use the matsutake mushrooms in your inventory to complete action "Matsutake Broth". Wait another 3 cycles (again unable to buy food from him during this time), go through one more dialogue with Emphis, and the achievement should unlock after the dialogue finishes.

This is unlocked after completing the long-winded quest line for Emphis the Food Vendor. You will need to unlock the greenway (by paying the one-time unlock cost for the ferry) and advance your progress with Riko the Botanist to be able to grow the mushrooms required for Emphis.

I suggest doing this quest-line early as it is not directly tied to any endings and does take some time to progress