I recently spent three weeks pretending to have sex with an imaginary monster that lived in my utility cupboard.

The Beast, you see, is a card game - "An Unsettling Erotic Game For One", as it describes itself on a title card, which also states, in large font: "Fear the Beast. Love the Beast." - brought forth with much love, and playtesting, and help from people like Jason Morningstar, a well-known indie developer and not, as the name may suggest, a medieval weapon. I heard about it in February when James Wallis, another tabletop game designer, did a talk at the independent games-themed event VideoBrains. "It's the most interesting game about sex I've come across.This is not a nice game about sex," he said of The Beast. "This is quite a scary game about sex."

It works like this: on the first day you fill out your 'Beastionnaire', which helps you define your beast - what it smells like, how it feels, and, importantly, what about it arouses you and what repels you. You then draw 19 cards from the deck without looking at them, and place them face down, with the Closure card (added to definitively end the game) at the bottom. Every day, for the next 21 days, you draw a new card, read the question on it, and write your reaction to it in a diary. When your diary is finished you read it back, and then destroy it or hide it. No one else may read it.

I spoke to Aleksandra Sontowska and Kamil Węgrzynow­icz, the Polish developers for whom The Beast is their first published game. They're partners in every sense, and despite the unsettling nature of their game they're bright and lively, often talking in tandem to expand each others thoughts, which is all helpfully thematic of the game itself. They're aware The Beast is not conventionally nice. The decision to make it for one player was initially to ensure it was safe (the same sort of scenario for two people could, they felt, allow one player to abuse the power they had over the other) but a side effect was that they could push other aspects further. "We can make it also a bit scary, horrible, awful, discomforting," explained Sontowska, "Because you're feeling safe that you can leave the game at any time."

What the pair have ended up making is an intensely personal and uncomfortable experience, delving into the duality of sex and relationships - how they can be at once arousing and disgusting, happy and sad - and the secret thoughts we keep hidden. The game itself has two intertwined elements, each dealing with one side of your interactions with your beast. The questions on the cards are a mixture, some with a more social, psychological aspect, others purely sexually explicit, that's perhaps also reflective of the game having two creators; Węgrzynow­icz says one of his first inspirations for The Beast was the disturbing, in-your-face feel of Cronenberg movies like The Fly, and that it was Sontowska who initially introduced the emotional elements.

Those parts can resonate strongly. Another player I spoke to, Caitlynn Belle, told me the relationship that grew with her Beast became more romantic as time went on. "I got kind of concerned for it, and I felt kind of bad about some of the things I was writing, and wished everything would go well, but it didn't," which is particularly interesting when you remember Belle was the one in control of what happened. Belle is a designer of "weird little games", many of which muck around with structure or require a component from the real world (an email inbox; an unfamiliar building at night) to play, and broke one of the cardinal rules of The Beast by posting her diary entries online as audio logs.

"There's an honesty that you can't escape from," she said. "You have to take all the parts of the beast with you whenever you do anything with it." We both saw the strange kind of understanding we developed with our beasts as having parallels with how relationships, and the contrasts within them, can play out in real life. "Whoever you end up with in a relationship is always going to have some, hopefully not monstrous parts to them, but some bad in there as well." But even though Belle had an audience for her game of The Beast there still wasn't a relationship with another, real, person.

The beast (disney)

"The beast is not a character in the story. She's not a protagonist, I'm the protagonist. Everything is from my point of view," Sontowska pointed out. "There are no questions about what the beast feels. There are questions about what the beast did or does." Reading back through your diary is an explicit rule to follow as part of the game, and what you're actually left examining are your own interpretations of the cards. You may be surprised what you find there.

One of the key inspirations for Sontowska and Węgrzynow­icz were the secret double lives people lead, often relating to sex and sexual desires; think BDSM enthusiasts who don't publicise that they like to squeeze into talc-dusted latex and be recreationally spanked at weekends (though Węgrzynow­icz says people who know and are comfortable with their fetishes are sometimes disappointed that the game isn't just a mastubatory aid). Yet, as previously mentioned, there's a strong physical element to the game alongside the psychological. It's another conflicting reality of sex which the pair find interesting.

"The body is not a very cool thing. It vomits, it spits, it has a lot of loose, flabby things. It's not really sexy all the time!" Sontowska said. "And at the same time you have this beautiful person with feelings, and sex gives pleasure, and so on." They mention the absurdity of relationships they've read about where, for example, one partner didn't want to see the other washing before having sex, and thus presumably dispelling the illusion that the person he wanted to get nasty with was secretion free and naturally smelled of soap. With The Beast, Węgrzynow­icz told me, "I wanted to break the taboo about physicality, physiology. I wanted to go in your face and shout 'Yes, sex can be dirty! Yes, sex can be physiological!'"

Depending on how you shuffle the cards your experience of The Beast can be very different. For my playthrough the deck ended up front loaded with social questions: What does the Beast feed on?; The Beast gave you a gift. What is it?; In what way and how often does the Beast show affection? It meant I was more emotionally 'bought in' by the time the explicit questions arrived, which are an integral part of the game: it's the constant pull between the emotional and the physiological that makes it so unsettling. You're continually forced to think about, and describe in some detail, the practical necessities of making the beast with two backs with a beast which may, conceivably, already have two backs, before being pulled back to a question about your feelings. It's almost like being in a (weird, fucked up) relationship but performed in an intense microcosm and with yourself. When the first explicit question appeared in my deck it was a very challenging moment.

According to Węgrzynow­icz this is a normal part of the process. "We've found out there is - no matter what kind of questions you pick - there is usually the same story arc. There's a honeymoon," he said, laughing. "'I can do everything, it's great, we're breaking everything, we're breaking the rules!'" Then, somewhere between the fifth and tenth day comes a question Węgrzynow­icz says, in a nice turn of phrase, "Pinches the balloon, and you have to push through the difficult things."

I managed to push through until the end, although I kept my beast diary with me in my bag at all times like a child I'd raised incredibly poorly: not trusting anyone else to look after it as well as embarrassed by the physical evidence of how much of a fuck up I am. Part of the process of The Beast, though, is learning how much of a fuck up you are and accepting it. Although Sontowska and Węgrzynow­icz want a player to get a memorable experience from The Beast, they also hope they'll get some outside perspective. "For me it's that they would think back on what happened in the game outside the game. As if the beast really was!" said Sontowska. Węgrzynow­icz expanded on the thought: "To actually evaluate the things the player did to the beast with someone else's eyes," he said. "To actually see if they wanted to be in this kind of relationship."

After playing The Beast I certainly discovered things lurking in my psyche that I wasn't entirely aware of. The game isn't so much a way to unleash your darker, complex feelings, but more letting them out of the basement to examine for a bit, with the suggestion that you could take them out for a walk sometimes in future if you like what you see. Belle told me she got rather attached to her beast: "It sounds like this absolutely horrifying thing but after spending twenty something days with it I really missed it when it was gone."

The awful Hollywood-esque truth of it, of course, is that even after the game is over The Beast never leaves you because... it was you all along.

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