R ealism, contrary to appearances, isn’t a form closed off to horror. The stories in ’Pemi Aguda’s debut collection, Ghostroots, a finalist for the 2024 US National Book award, rivetingly bore out this fact. Neither strictly realistic nor wholly supernatural, they seized on ordinary events pulsing with sinister possibility: a mother distraught at her inability to produce milk for her newborn wonders whether her unresolved feelings over her husband’s infidelity might have poisoned her body; a young woman prone to violence fears she is inhabited by the spirit of a wicked ancestor; a driver who runs over a pedestrian can’t shake off the feeling that her own daughter will be next to die. One Leg on Earth, as the title suggests, is similarly a liminal creature, although it flirts more openly and ingeniously with darkness. It follows a young woman, Yosoye Bakare, newly arrived in Lagos to intern at an architecture firm involved with building Omi City, a state-of-the-art enclave on land reclaimed from the sea.…