Rhianna Pratchett, 36, is a video-game scriptwriter. She lives in Islington, north London, with her two cats, Pinky and Perky. Her father is the novelist Terry Pratchett

"I grew up playing video games with my father. At the age of six, I’d sit as he played on the console, drawing maps on a notepad and telling him where to direct the little pixelated man. Now, it’s my job to brainstorm, story edit, and write scripts for computer games. This means I work with developers to help flesh out the back story of characters, or to construct a narrative arc. It’s not like writing a novel from scratch. Instead, I work with developers throughout the making of the game to ensure all the elements – setting, characters and dialogue – work cohesively.

I work from home – my office can be anywhere that hosts me and my laptop, really. So I wake up at about 9.15am, have a quick shower, pull on some black jeans and an anime T-shirt, and boot up the computer. I read over my emails while having a breakfast of yoghurt and muesli.

My morning is spent talking to clients about how they see characters developing, or discussing what they’d like me to write for them. I’ve written for everything from comedy games to combat games, but most recently I wrote the script for the new Tomb Raider game. The main things I work on are ‘story bibles’. When you have a big fictional ‘world’ in a game like The Sims, for example, the ‘story bible’ or ‘world bible’ is a document of everything that goes on in that world: the characters’ back stories, how they feel about one another and every detail of the game’s setting, from the smallest animal to the largest monster. It’s a Dr Frankenstein-type way of working. You’re given a box of body parts and you have to breathe life into them.

Around 1pm, I head to the kitchen to make lunch – well, heat it up really. My boyfriend Louis is a fantastic cook and we love shopping at the organic market in Islington, so he makes me something like chilli or soup.

I have an office at home but I rebel against it, so in the afternoon – if I’m not out at meetings – I move around from room to room. The flat is filled with memorabilia from video games and films. I have bookcases heaving with DVDs, sculptures of Tomb Raider characters and little figures from the shop Forbidden Planet. My walls are covered in posters from the Alien series, too. It’s a bit ‘teenage boy’, but I take my job very seriously. I’m passionate about what I do and have worked hard to forge a name for myself in the gaming world.

Games fans ask how I got my job. The answer is a lot of work. I started out as a gaming journalist, writing for games magazines and papers like The Guardian and The Sunday Times. Then a friend asked me to be a story editor for one of their games. I really enjoyed it so used my journalism contacts to look for story-based work and it went from there. But I don’t just write gaming scripts. I’m always juggling projects. I adapt novels into screenplays, write comics and have just set up a production company called Narrativia with my dad.

I was very close to him growing up and his fascination with computers and robotics really influenced my choice of career. Dad’s always talked to me about his writing, it helps him work. He is doing as well as can be expected for someone with PCA Alzheimer’s but he can no longer type and so either his PA types for him, or he uses Talking Point speech-to-text software. He seems to really enjoy speaking stories instead of writing them and narratively he’s as strong as ever. The ideas never stop flowing.

I held back from getting involved with novel writing for a long time because I wanted to make my own mark and find my own way. People will always say, ‘Well, it’s just because she’s Terry Pratchett’s daughter.’ But I’ve got a lot to contribute because I’ve built up a portfolio in an arena that’s very different to Dad’s. I’m lucky that my work is also my hobby.

My evenings are spent out of the house, trying out new games or watching films with friends. Louis is trying to get me to eat fewer sweets and take care of my diet so he makes us something hearty like a lamb stew or a curry, before we eventually go to bed at about 1am.”

Tomb Raider is out 5 March; tombraider.com