The story is a familiar one: a male settles into cosy domesticity and soon piles on the pounds. "This isn't the person I fell in love with," laments the female as her newly bulky partner lumbers towards her, physical affection on his mind.
The refrain is also, it seems, heard in the giant panda world, where excess weight has been identified as an obstacle preventing the notoriously sex-shy creatures from mating.
According to reports from Thailand, keepers at Chiang Mai Zoo, in the north of the country, have put Chuang Chuang on a diet in their latest attempt to get the male panda to mate with his companion, Lin Hui.
"Chuang Chuang is gaining weight too fast, and we found Lin Hui is no longer comfortable with having sex with him," the zoo's chief vet, Kanika Limtrakul, explained.
While human equivalents may cut out beer and takeaway curries, Chuang Chuang - who weighs more than 23 and a half stone against Lin Hui's slimline 18 - is now being given only bamboo leaves and is missing out on the plant's richer shoots.
The episode is a headache for the zoo, which paid more than £100,000 in 2003 to "rent" the pandas from China for a decade. As well as the extra revenue from visitors, the zoo is desperate to get a panda cub of its very own.
In 2005, the zoo staged a mock wedding between Chuang Chuang and Lin Hui in their enclosure in an attempt to get them in the mood. It has reportedly also considered showing them "panda porn" - videos of other giant pandas engaged in mating.
The originator of panda porn - and virtually every other trick in the giant panda book - is the famous breeding centre at Wolong Nature Reserve, in south-western China's Sichuan province.
As this paper's Jonathan Watts reported last month, scientists at the centre say they can now breed captive pandas at will using new techniques. These include one not yet been tried out on Chuang Chuang, to his probable relief: the electrified anal probe.
This is, of course, all carried out in the worthy cause of preserving this most emblematic of all endangered species.
But are the indignities even necessary? A major survey last year said there may be twice as many giant pandas living in the wild in China than previously thought.
