A kotatsu company has announced a surprising new feature. The new kotatsu can stop people from leaving.

The company says the feature is very simple. When a person puts their legs under the kotatsu, the kotatsu becomes warmer and softer. Then the person feels too comfortable to move.

"It is not a bug," a company worker said. "It is a feature."

Many families are interested in the new product. One father said he sat down for five minutes and lost three hours.

A high school student said the kotatsu was dangerous. "I wanted to do my homework," she said. "But the kotatsu told me to rest."

The company says the kotatsu does not really talk. However, many users say they can hear a quiet voice. The voice says, "You can start tomorrow."

Some people are worried. They say the kotatsu may make winter homework impossible.

The company is now making a new model. It will have a button called "Emergency Exit."

However, the button will be outside the kotatsu.