In the battle for a slice of the ¥8.1 trillion ($72 billion) retail electricity market, Japan's biggest power companies are lining up against a cuddly bear, a fluffy white dog and a gorilla in business attire.

As the government starts fully liberalizing the power market in April, new entrants are jumping on the yuru-kyara (mascots) bandwagon to lure new customers away from its 10 regional monopolies. Tokyo Gas Co. has introduced a new yellow and white bear character called Denpa-cho, while wireless mobile carrier SoftBank Group Corp. has deployed Oto-san, the white dog named "father.""In the West, adults tend to avoid cute characters that seem childish, but in Japan these characters are thriving," said Tatsuya Yamamoto, a Tokyo-based character consultant with the advertising and public relations juggernaut Dentsu Inc. "Businesses use them because children, as well as adults, recognize them."

In the land of Hello Kitty and Super Mario, mascots promote everything from motor fuel to the military. Now they've been enlisted in the fight for a piece of Japan's shrinking electricity market amid Prime Minister Shinzo Abe's efforts to boost corporate competitiveness. Power usage last year fell to a 17-year low as households and businesses conserved electricity amid stagnant growth and a falling population.