Nothing But Blackened Teeth is horror. I bought my copy new.
Review:
Not too long ago, Cat took a break from her university studies to take care of her mental health - it had gotten bad enough that she was feeling suicidal. Now she's on a trip with the people she's closest to: Phillip (a rich white guy Cat was once briefly in a relationship with), Faiz (another guy Cat was once in a relationship with, although they learned they made better friends than lovers), Talia (Faiz's fiancee), and Lin (possibly another guy Cat was once in a relationship with??).
Talia has always dreamed of getting married in a haunted house, and so Phillip has paid for them all to travel to Japan and spend some time in a old Heian mansion supposedly haunted by a bride whose groom died before they could be wed - the bride was buried alive in the house, to keep the house standing while she waited for her groom, and every year after her death they buried a new girl in the house, to keep the bride company. Cat is there because Phillip and Faiz were there for her when she needed them the most, but the tension is palpable - Tina only barely tolerates Cat for Faiz's sake.
As you'd probably guess, getting married in a house haunted by the ghost of a bride who never got to marry her groom isn't a good idea, and things rapidly go south.