Next to working as a dolphin trainer or ice-cream flavour tester, being Shrek's best friend must be the average six-year-old's idea of the best job in the world.

But that, as they say, is not all. During the day, I occasionally slip round the corner to pal with Po, the Kung Fu Panda. Getting high-fives from the penguins from Madagascar any time I want? Not a problem.

There is a more rugged side to what I do too. I have to keep an eye out for creeps who think that the price of a ticket to the Universal Studios Singapore theme park in Sentosa includes a feel of Princess Fiona's bottom.

The royal rump is definitely out of bounds to commoners and while I may not have the power to clap them in irons, I can exile the blackguards from the kingdom of Far Far Away. In short, I am a "character escort".

It is a Monday morning as I slip on a forbiddingly black polo shirt with "Entertainment" printed across the back. It is the word I have promised to serve and protect. I am the policeman of fun, the custodian of enjoyment.

My job, along with the 60 or so of my character escort colleagues, is to protect Princess Fiona and the rest of the characters - Shrek, the Madagascar crew, Po and others - from being mauled, poked or pushed when they prance around the park or stop for photo sessions.

The way I see it, we are the thin black line protecting these fragile creatures of fantasy from the real world, a nasty place where male guests can get too friendly with our Marilyn Monroe and Betty Boop, or who might punch a panda just to see if he knows gongfu, or pull on Woody Woodpecker's beak.

I follow the staff to pick up costumes and uniforms from a place called "back of house". It is like a giant vending machine. The employee taps his pass and a motorised belt will swing clothes slowly and majestically past a collection window. The computer will stop the belt only when the right uniform appears and release the hanger.

My clothes, however, are already prepared for me. Once I am in my polo and roomy brown shorts, I head to one of the parks' several "green rooms", an old theatrical term for places where the performers change and rest. This particular room is for Gloria the Hippo, Alex the Lion, King Julien the Lemur and the penguin group, the stars of the Madagascar movie franchise.

Five times a day, the group will trot outside, dance and pose for photos with the guests. Our job as escorts is to whip some sort of order into the melee that will by now have engulfed them.

"Please form a line over there," and "Sir, Madam, the back of the line is over there," we say.

Another handy line: "Could I please take the picture for you?" One reason we like taking dad's camera is so he can get into the photo with his family in one shot, not two. Because of the heat, each session is limited to 20 minutes.

"Please, he has been crying," begs one woman, pointing at her son, who looks about 10. I have just told her that Puss In Boots, the Latin lover character from the Shrek movies, needs to return to the magical castle. She is too late to join the photo line. She is being overly dramatic, I note, because her son does not seem to be crying at all.

Walkie-talkie power trip

But she will not give up asking. If I did allow her, the dozen or so people behind her would want to join too. She can come back in one hour for the next show, I tell her, but it takes some persuading.

Maybe it is the heat, already baking by 11am, that makes parents go slightly insane. A father, also blocked from the queue, storms away muttering, dragging his children with him.

It is the parents who behave like kids in a theme park, I find. The real kids are perfectly behaved.

It is easy to see how a person in my position can get drunk with power. I catch myself on more than one occasion with arms crossed, lips pursed and jaws clenched, looking like the guy everyone who has ever been to an outdoor concert hates - the bouncer with an attitude problem.

Ms Rachel Ong, 34, the stage manager in charge of all the street performers, brings me down to earth. The families who go to Universal Studios Singapore are there to spend a day having fun. Lighten up, she says. I try to curb my fascist tendencies after that pep talk, but the black shirt and walkie-talkie earpiece are like a power drug.

"If anyone makes a big fuss, don't handle it yourself. Step back and call security," she advises, perhaps wary of my growing appetite for control.

Later, at the photo line for Shrek and Princess Fiona, Ms Ong spots something. A man posing for a photo with the princess had done the classic pervy act. He squeezed her bottom.

The princess did not kick up a fuss, probably so as not to disappoint the dozens of families still in the photo line. Ms Ong takes the man aside and gives him a warning. I am right in front of the princess, but see nothing. Maybe, I even took a picture of the man with his family. I was still a long way off from being a real escort.

Soon it is lunch time and we retreat into the air-conditioning of the Mad Cafe, one of four cafeterias for staff secreted in hidden parts of the resort area. Employee meals throughout the day are free. At the table is Mr Liu Yi Zong, 22, a character escort of five months. Like the other people working there, he radiates an infectious enthusiasm, the zeal you see in the eyes of people who know they are doing something new and interesting.

The way he explains it, I probably missed the moment when the man misbehaved because I failed to keep eye contact with the princess.

"You need to have chemistry with the character," he says. The mascots do not speak, so as not to break the illusion. Hand or eye signals that tell the escort when, say, the character feels mobbed or threatened, or needs to take a break immediately. A few months ago, during a particularly crowded day, Woody Woodpecker gave a hand-across-throat signal. Mr Liu rushed him to the rest area. Woody, as it turned out, was close to having heatstroke.

My day ends close to 6pm, just as the crowd is reaching its peak. The park, which opened in February, is now in its soft-opening period and weekends are packed. It needs more Mr Lius and will be holding auditions for character escorts and more next month, with details on the Resorts World website.

Successful candidates will get the chance to save fairy-tale princesses from harm on a daily basis. How many jobs allow you to say that?