‘Exorcizamus te, omnis immundus spiritus! Omnis satanica potestas, omnis incursion infernalis adversarii, omnis legio, omnis congregatio et secta diabolica!’

Tom rears up and spits at her. The saliva glistens and drips from her cheek, but she doesn’t wipe it away. She keeps her palms pressed to his chest, her expression grimly determined. Tom writhes harder, his body twisting and turning, and then his head snaps in my direction. He glares at me, his face full of hatred, and cold foreboding washes over me. I can feel the malevolence seeping out from him. Some human instinct tells me that whatever’s inside him is beyond all reason or understanding. It is evil itself.

I step back and Morgan beats her wings furiously. She looks like a creature of the night about to rip out his throat. Tom bucks and fights but she holds him down. He gnashes his teeth, his legs thrashing under the covers, and I silently plead for him to stop. But he doesn’t. He struggles and kicks and eventually manages to throw her.

She tumbles to the floor and in the next second he sits up and makes for me. Morgan leaps on top of him, landing with her bare feet on his hips and her hands on his shoulders. She screeches and the sound is like nothing I’ve heard before: a wail of rage so terrifying it could rip the flesh from a rodent’s back and slice the scales from a fish.

She shoves him onto the bed. ‘Exorcizamus te, omnis immundus spiritus!’

His body arches and his lips open, letting out a stream of darkness that swirls and curls around on itself like a snake. A foul smell rolls through the room – rotting flesh mixed with the acrid stench of sulphur, and I cover my mouth and fight the urge to gag. Morgan pushes up his shirt and something is wriggling beneath his bare chest and stomach. Faces appear under his skin, pushing at his flesh like they’re trying to get out.

She reaches into the swirl of darkness coming from his mouth and pulls out a shadowy, severed head. Holding it with one hand, she claws at it with the other, slashing it to pieces. She grabs another and another, clawing and biting. Her head jerks from side to side as she pounces on each monstrous form. She snarls and snaps, claws and rips, tearing the darkness to shreds and sending it scattering into the corners of the room like cockroaches.

Eventually the stream of darkness slows and Tom slumps back onto the mattress, his chest heaving. Morgan licks her lips and beats her powerful wings, her long hair flying wildly as she twists her head from side to side, ready to swoop at the smallest movement.

I call out, my voice weak. ‘Is it over?’