TOKYO—At the Manuscript Writing Cafe, people on a deadline pay to put themselves under the gaze of a manager in hopes of curing writer’s block.

Joe Sasanuma, a lawyer at a technology company, is under orders from his publisher to complete a legal book by the end of the year. Alas, the words to explain the contractual obligations of cloud-computing providers haven’t flowed effortlessly. So Mr. Sasanuma has been visiting the cafe.

The cafe’s co-owner, Takuya Kawai, directs his customers to set a goal for the day and, if requested, prods them to get on with it. If they fail to meet it by the time they leave, they have to pay a fine equivalent to $22. It’s an honor system, says Mr. Kawai, but it seems to work.