He's The Devil by Tobi Coventry

Simon has always been a good boy. He’s invariably employee of the month at the seasonal small plates restaurant where he works, he neurotically tidies his home, he keeps on top of repairs on behalf of his twenty-something, permanently-abroad landlord and tries to do right by everyone. But when his best and only friend, Josh, moves out of their shared flat, Simon is lonelier than ever – until in moves a new flatmate, the strange (and strangely sexy) Massimo.

But Massimo’s brought something with him. Odd sounds emerge from Massimo’s room, smells of earth and meat drift through the corridor and Simon’s nights fill with disturbing and tantalising dreams. Massimo is awakening something in Simon, something wild and exciting and horrifying that could be the end of him – or maybe a new beginning.
But whatever’s in Massimo, whatever’s in the flat, isn’t finished. It wants more …
 
He's the Devil is a wickedly funny, chillingly suspenseful modern day horror story, painfully relatable to anyone who has ever had to share their living space with someone they'd honestly just rather not share it with.
 
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'Magnetic, claustrophobic, wickedly alive' LUCY ROSE
 
'Horny. Gory. Relatable'. KIRSTY LOGAN