Nadia named her sourdough starter Gerald, the way you name anything you have to feed twice a day and slightly resent. This morning, taped to his jar in flour-dusted handwriting she did not recognize, was a note: WE NEED TO TALK ABOUT THE THERMOSTAT. Gerald had no hands. Gerald had no pen. And yet there it was, the tape still slightly warm.

Nadia decided the bravest thing was to answer. She grabbed a pen, wrote "WHAT ABOUT THE THERMOSTAT?" on a sticky note, and pressed it to the jar. Then she stood back and waited, arms crossed, feeling ridiculous. A bubble rose to the top of Gerald and popped, like a tiny throat clearing.

Nadia tried a test. "If you're really alive," she whispered, "spell my name." She waited. The flour dust on the counter began to shift on its own, pushed by nothing, until it spelled N-A-D-I-A, then drew a little heart. She sat down hard on the kitchen floor. "Oh no," she said. "I love you."

Touched, Nadia made a deal. She bought Gerald a tiny heated mat and a nicer jar with a window. In return, Gerald became the best roommate ever, rising the bread, warming the kitchen, and leaving sweet flour notes like HAVE A GOOD DAY. They lived happily, one woman and one cozy, opinionated blob.