“Sumikkogurashi” are the characters living a quiet and solitary life in the corner and the key phrase is "koko ga ochitsukundesu," meaning "I feel comfortable here."

When you ride a train, you seat yourself into a corner seat. When you go to a café, you will choose a table in the corner as far as you can.

Don't you find yourself relaxing in corners? Many Japanese people feel this way, and that feeling has been personified in the Sumikkogurashi characters.