H.L. Day’s Demon Inside is a fast-paced, action/adventure paranormal romance set in London featuring likeable but flawed protagonists, an interesting plot and plenty of snark and steam. It has a few weaknesses – the romance feels a bit rushed and some elements of the story are a bit predictable – but it’s an entertaining read that kept me turning the pages, and I breezed through it in a couple of sittings

Jude Campbell has been able to see demons since he was a small child. In this world, demons possess human bodies and thus look completely normal on the outside, but Jude can see beyond that to the demonic ‘glow’ that radiates from their features. Unhappily, this ability has led to Jude’s being believed to be mentally unstable and a psychiatric history full of scepticism, doctors, therapists, drugs and an endless parade of different treatments. It’s perhaps not surprising that his parents never believed him – seeing demons is pretty fantastical after all – but they’ve never made any secret of their belief that he’s crazy, and at the age of sixteen, they had him sectioned (committed to hospital under the Mental Health Act), something for which Jude has never forgiven them. Now thirty-five, he’s estranged from his family – although he does have some contact with his younger brother – and is kind of drifting through life, struggling to hold down a job or a relationship, and sometimes even wondering if he really is mentally ill, if everyone around him is right and he’s the one in the wrong.

By rights, Dante Moretti should never have been born. Half human, half demon, he is a unique entity, one the demons intent on killing him call “Abominato”. Fighting off demons and sending them back to hell (while trying not to kill the host bodies) has been a constant in his life, but lately, the attacks have become more and more frequent, and he doesn’t know why. Given the increase in numbers, Dante really needs a better way of identifying his targets; he can’t see demons, he can only sense them, and even then, not until they’re really close. The irascible Father Rory McCormick – the closest thing to a father Dante has ever known – is following leads, trying to discover if the rumours about there being someone out there who is actually able to see demons are true, and also to see if he can find out the reasons for the increased frequency of the attacks.

Rory tells Dante he’s found two more possibilties – one a homeless man, the other… not. Dante is instantly captivated by the photo of the second man – by his arresting face and strong jaw, his deep chestnut hair and chocolate brown eyes – although hope wanes as Dante reads through the man’s lengthy history of psychiatric treatment and lists of medications. So many of the rumours that have reached Rory’s ears have led to people who have turned out to be nothing more than harmless crackpots, but this guy seems like more of a waste of time than most.

But when Dante hears a name on the “Demon Radio” (demons are able to communicate telepathically, and even though he’s only half demon, Dante is able to hear and interpret some of their mental traffic) he realises that the man in the photo – Jude Campbell – is in grave danger. Rory manages to find out where he is – a hospital appointment – and Dante sets out to intercept him and get him out of there before the demon assassins turn up.

Jude doesn’t know why he’s bothered to attend his doctor’s appointment, although things start looking up a bit when a tall, dark and handsome nurse shows up In the consulting room. But Jude’s pleasure is short-lived when he realises that the man isn’t human – even though he doesn’t look like any other demons Jude has seen, he definitely is one. Terrified, Jude tries not to panic – but then the demon tells him he’s there to help him, tells him not to go home because they are waiting for him, and then just… walks away.

Scared and confused, Jude isn’t sure where to go if he can’t go home, and is walking towards the bus stop when he realises he’s being followed. Backed into a corner and with nowhere to run, Jude expects he’ll shortly be breathing his last when the nurse/demon from the hospital appears, grapples with the demon and overpowers him while speaking some sort of incantation in a language Jude doesn’t understand.

After their dramatic meeting, Jude warily agrees to accompany Dante back to his flat, where Dante fulfils the promise he made to tell Jude as much as he knows about what’s going on. For the first time in his life, Jude feels validated, a huge wave of relief rushing over him as he realises that he really isn’t insane and that demons are real. That they’re intent on killing him is perhaps not such great news, but he agrees to help Dante and to learn how to fight and eradicate demons himself as well. There’s a definite attraction sparking between the pair from the start, but Dante is determined to resist it, warning Jude he should never forget that he – Dante – is only half human, that he is in a constant battle for control with his demon side… and that he fears what he might do should he let that part of him gain the upper hand.

But when they’re forced to go on the run, the close proximity and constant, shared danger bring about a new closeness and understanding that starts breaking down the barriers between them and makes it impossible for Dante to continue to deny himself the thing he wants most. Things heat up quickly, and they both attempt to tell themselves that what’s happening is just a casual fling born of circumstance, all the while knowing deep down that it’s nothing of the sort. Soon, they start to notice subtle differences in each other – Jude realises he is able to calm Dante’s inner demon and that he’s suddenly able to move much faster than a human should be able to, and Dante discovers that holy water no longer burns him as it does with other demons. Something about them – about their connection – is changing them, but what? And, more importantly, just what are they becoming?

Demon Inside is a thoroughly enjoyable read with a twisty plot and engaging characters who are complex and well-drawn. The author does a good job of presenting Jude as someone who’s been beaten down by life, and I liked the way the realisation that he’s been right all along – even though it’s put him in grave danger – finally prompts him to come out of the shadows he’s lived in and become more confident in himself. Dante’s life up to this point has been no picnic either; bounced around foster homes until ageing out and finding Rory, he’s a loner, too, rarely allowing himself connection or intimacy for fear of what his demon side will do if he’s not in rigid control. The romance between Jude and Dante develops a little faster than I’d have liked, although as the story progresses, it becomes clear that there’s more than a whiff of ‘fated mates’ about it – yet while destiny may well have had a part to play in their finding each other, there’s no question that their ability to be their true selves with one another is an equally important factor in their love story. Dante’s relationship with Rory is nicely done and full of snarky affection, and I was pleased at the hope extended for a reconciliation between Jude and his brother Fletch.

The main criticisms I have about Demon Inside are that some aspects of the plot are a bit predictable, and that there are some plotlines that are either left hanging or forgotten about (Rebecca’s murder) or handwaved away (the secret Vatican society Rory belongs to). But those are outweighed by the things the book does right – the pacing, the action, the characters – and I really enjoyed reading it. If you’re in the market for a standalone paranormal romance, this one is definitely worth checking out.