The letter to Jetstar Airways, which has since gone viral, was penned by a furious Rich Wisken.

Rich was flying Jetstar from Perth to Sydney – which is a four and a half hour flight - and had paid an additional $25 for a seat with 'extra room'.

What he hadn't banked on, however, was a morbidly obese man to do the exact same thing.

And he was, as you'll see from his letter below, extremely unhappy about it.

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The letter reads:

Dear Customer Relations,

Do you like riddles? I do, that’s why I’m starting this letter with one.

What weighs more than a Suzuki Swift__, less than a Hummer and smells like the decaying anus of a deceased homeless man?

No idea? How about: what measures food portions in kilograms and has the personal hygiene of a French prostitute?

Still nothing? Right, one more try.

What’s fat as f@@@, stinks like sh@@ and should be forced to purchase two seats on a Jetstar flight?

That’s right, it’s the man I sat next to (or to be accurate, under) from Perth to Sydney yesterday!

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As I boarded the plane, I mentally high-fived myself for paying the additional $25 for an emergency seat. I was imagining all that extra room, when I was suddenly distracted by what appeared to be an infant hippopotamus located halfway down the aisle. As I got closer, I was relieved to see that it wasn’t a dangerous semi-aquatic African mammal, but a morbidly obese human being. However, this relief was short-lived when I realised that my seat was located somewhere underneath him.

Soon after I managed to burrow into my seat, I caught what was to be the first of numerous fetid whiffs of body odour. His scent possessed hints of blue cheese and Mumbai slum, with nuances of sweaty flesh and human faeces sprayed with cologne – ‘Eau No’. Considering I was visibly under duress, I found it strange that none of the cabin crew offered me another seat. To be fair, it’s entirely possible that none of them actually saw me.

Pinned to my seat by a fleshy boulder, I started preparing for a 127 Hours-like escape."

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The letter continues:

Imagine going out for dinner and a movie, only to have your night ruined by a fat mess who eats half your meal then blocks 50% of the screen. Isn’t that exactly the same as having someone who can’t control their calorie intake occupying half your seat on a flight? Of course it is, so that’s why I’m demanding a full refund of my ticket, including the $25 for an emergency row seat.

I’m also looking to be compensated for the physical pain and mental suffering caused by being enveloped in human blubber for over four hours. My lower back is in agony and I had to type this letter one-handed as I’m yet to regain full use of my left side. If I don’t recover completely, I’ll have to say goodbye to my lifelong dream of becoming Air Guitar World Champion. If that occurs, you will pay.

To discuss my generous compensation package, email me at: ****__._

Over recent days, Rich’s letter to Jetstar has gone viral globally, featuring on numerous press websites across the world.

No sign of any reaction from Jetstar yet... or, in case you're wondering, the unnamed obese gentleman who was sitting next to Rich.