At most such establishments, it's the post-work rush that brings in the most cash, with tired and harried professionals dropping by on their way homes to pet and play with the animals as a way of relieving stress.

But now the purrs of delight may be getting quieter.

A revision to Japan's Animal Protection Law, due to come into force on June 1, will slap a curfew on the public display of cats and dogs, forcing cat cafes to shut up shop at 8 p.m.

"There's this new revision which says we should be open from eight in the morning until eight at night. After 8 p.m. we have to put the cats in the back, away from the customers, and close," said Hiromi Kawase, the owner of one Tokyo cat cafe.

"Everybody knows cats are really happy in the evening, with their big, cute eyes. So I just can't understand why the people at the top are ignoring this. It's really strange."

Cat cafes have long been popular, catering to the many cat lovers who can't keep the animals at home because of strict housing regulations that forbid pets in many apartments.

Visitors to Kawase's cafe pay about 1,000 yen an hour to play with any of her 24 cats, who dart around the room chasing toys or sleep in baskets set on tables. Drinks are priced from around 300 yen each.

The government says the real targets of the tighter animal protection law are late-night pet shops, which often sell dogs and cats around the clock. The animals are kept in small cages under bright lights that are never switched off.

Kawase's establishment is far from a 24-hour operation. Her doors close at 10 p.m., but she says many of her customers only arrive around eight, after work, and stay through to the close.

"If I can't see the cats, well, I won't come. Of course I come here because they have cats," said Tatsuo Karuishi, 41.

Karuishi visits the cafe at least twice a week, usually checking in at around eight, as does fellow feline fancier Ayumi Sekigushi.

"It's a great place, it calms the stresses of working life," said Sekigushi, 23. "If this law goes, through that enjoyment is going to disappear. It's a real shame."

While Kawase says the lost business hours will take a toll on profits, it's what that might mean for her cats that worries her the most.

"If our business hours go down and we lose two hours of profits, of course it's going to affect us, but it'll also affect the cats," she said.

"You know, in getting them all the things they need, like the correct amount of food and proper nutrition."

(Editing by Elaine Lies and Ron Popeski)

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