First, you need the task on the right, which has two columns. Click on this story and you can follow it. Then start captain npc, right in front of the building materials store. Just move bricks and point, and then run away. When you come back, you can click them with a letter, and then run to the first floor, which is near autumn. You can find this Martha.

At the end of the game, when Stella sent away all the souls, lush green grass spread all the way from the captain's room and opened a talking and hugging flower. This flower is Stella's sister, the last soul or echo.