The day in question was interesting for me because everyone was dressed up as animals. We all put on costumes that displayed our desired personalities. There were no specific instructions and we could all choose any animal, but naturally we all made the most of the opportunity.

Adam was a leopard. He has an inferiority complex and it would be too obvious for him to dress up as a tiger. Chopsticks was an ironic hyena. There were lots of minxy cats and boisterous apes. I was a lynx. I made a mask from orange fur with black stripes. It had long pointed ears with white tufts at the end. We were going on a trip to the Natural History Museum, to celebrate Chopsticks' twenty-fifth birthday.

We had a lot of fun when we got to the museum. We had alcohol mixed with fruit juice in our water bottles and most of us were getting drunk. Everyone took notice of us. Some people pretended that they'd seen it all before. Children loved us and we had fun teasing them. The apes got overexcited in the taxidermy section and were told to calm down by a good-natured museum attendant.

In the end we left without too much fuss. It was still early in the afternoon and we decided to take a detour through one of London's big parks. When we arrived, Chopsticks really got into role and started laughing hysterically and acting like an unhinged villain. I got on my hands and knees to prowl around a bit, looking wise and demonstrating my cunning and hunting prowess to the cats. In the end I got bored and sat on a patch of soft summer grass and made a cigarette.

At that point I noticed a strange group of people a short distance away. They had brought a picnic but I could see they didn't have much good food. It was mainly sliced bread and multipacks of frozen burgers or fishfingers. Unsurprisingly none of them were eating. They didn't interact with each other much and I wondered what the purpose of their trip was. One of them had a huge pile of newspapers that he was systematically working through, and another was assembling a volleyball net but she was tiny and the task was clearly far too difficult for her. As I carried on watching them, I saw that other people in the park were avoiding this group of misfits.

I was drawn to the group. One of them especially interested me, who was reading a old yellow-paged edition of Dostoevsky's The Brothers Karamzov. I had a similar copy in my rucksack and had been conspicuously reading it on the bus while my friends entertained and accosted the lunchtime travellers. This individual was even more removed from the rest of the group and, crouching over the book, seemed to prefer solitude. I couldn't determine whether this person was male or female.

The others in my group were also drawn to this odd jumble of weirdos. We aspire to be on the outskirts of society and are not interested in the normal trappings of modern life. Anyone demonstrating a natural disregard for politeness and conformity is held in the highest esteem.

I was turning these thoughts over when one of the funny group – a girl with a lopsided haircut that might have been a wig - got up from the picnic and came over to ask me for a light. I suppose I must have looked unusual dressed as a lynx, but we were obviously having a fancy dress party, which was not so strange. As she approached she proffered her cigarette, not in the normal way, as you'd hold a cigarette in your mouth before lighting it, but out in front of her. Naturally I got out my lighter and lit it, and she held the end of the cigarette in the flame until it was charred, then scurried back to the group.

During this time Adam had entered into an interaction with one of the strangers. I decided to join them and ask the Dostoevsky reader about the book. I was tired of my friends' mobbishness, and wanted to rescue some value from the day. But when I got closer, a weird feeling overtook me, because the reader's face was unusually similar to my own. The person was clearly male. He looked at me – he didn't seem to have been concentrating on his book – and considered me with a steady gaze that communicated no emotion at all. He was sitting cross-legged, with his shoulders rolled forward and his hands in front of his knees.

Now I was confronting my doppelganger. We had to acknowledge our position, in front of each other, or it would have been very awkward. I couldn't see him very well through the eye holes of my mask, and my whiskers were obscuring my view, so I took off my mask to get a better look at him and try to start a conversation. He mirrored my action, putting his hand to his face, and once I had my mask off I could see that he actually had whiskers of his own, protruding from somewhere behind his cheeks. I realised, to my astonishment, that he was wearing a mask as well, with my blank face on it, and underneath the mask was a catty face.

As I stared at the lynx, which looked dapper in its grey slacks, it moved with a speed and accuracy that I felt intensely jealous of, and snatched my mask in its paw. It slipped on my mask, looked up at me for a brief moment and had lost all the eccentricity of the peculiar reader, before slinking off into a nearby bushy copse. It had clearly decided that the company of its friends was not worth sticking around for, and I could see its point. They were evidently not adept at holding a picnic in the park.

And I looked down and saw his mask of me lying on the grass, picked it up and tried it for size. It fitted perfectly, of course, and at once I felt more relaxed and at home. For the first time since the brief encounter with the lynx I checked what my friends were doing. They were all standing around, wearing masks of their own faces with their animal costumes, with the group of odd-balls nowhere to be seen. The party was over and, subdued and at ease, we got on the bus and went home through a purple sunset over London.