Unnatural Selection — Ann Somerville

Four years ago, Nick Guthrie nearly died from a brain tumour until he received an experimental treatment that saved his life, even though the treatment brought bizarre and permanent side effects. Now he drinks fake blood to live, and has had to have his new long canines capped, but it's a small price to pay to keep doing the job he loves. He's a cop, part of a London Met Police Murder Investigation team.

His current case involves trying to find the person ritualistically killing gay 'vees'. With no witnesses and no clues, the police are stymied, but Nick won't give up until their killer is found.

Complicating his life is Dr Anton Marber, an attractive, gay minor celebrity Nick saves from being kicked to death one night. Nick doesn't expect to see Anton again, but Anton is amazingly stubborn when it comes to things that are important to him, like Nick's case, Nick's diet and Nick's determination never to fall in love again.