Why a Nigerian boarding school?
Long corridors, strict rules, lights out at nine. For a story about a teacher you hear in the dark, there was only ever one setting.

The legend of Madam Koi Koi lives in boarding schools. That's where it's told, after lights out, by senior students to new ones. So the game had to be set in one.
A place built for footsteps
A Nigerian secondary school is a set of long, tiled corridors with classrooms off both sides, a hostel block, a staff room and a yard. Sound carries down those corridors. That made it perfect for a game where her heels are the most important thing you can hear.

Details people will recognise
We wanted anyone who went to school in Nigeria to feel at home, and uneasy. SS2 and SS3 classes. Bunks checked by a prefect. A punishment book. A Vice Principal's memo. A sick bay register where the matron writes down who couldn't sleep. A Principal more worried about the school's reputation than about the truth.
- Ikenga Memorial is fictional, but it's built from real school layouts: a main hallway, classrooms on both sides, the staff room, the Principal's office, the library, the sick bay and the hostel.
- The second floor is closed. Schools close parts of buildings all the time. In this one, nobody says why.
- The yard and the back fence matter. You'll see.
Closed in 2010
The school has been empty for years when you arrive. Chalk is still on the boards, chairs still face the door, and the roll call is still pinned up in the hostel. An empty school is one of the most unsettling places there is, because you know exactly how loud it should be.