I've labeled this "Fantasy" when "Horror" would probably be more appropriate: but the movie isn't straight-up horror, mixing ghouls into the modern world. And besides, I don't have - and don't intend to have - a "Horror" tag.
Based on a Manga, set in modern day Tokyo where ghouls (beings that look human but can only survive by eating human flesh) live among humans ... so long as they can hide their true nature. They're hunted by CCG, who are perhaps nastier than the ghouls themselves. Our main character is Ken Kaneki, a mild-mannered college student and book worm. When a date goes horribly wrong (she tries to eat him), he requires an organ transplant. Unfortunately, it turns out that the donor was also a ghoul, and this leaves him half-human, half-ghoul. Or so he's told: it seemed to me he was all ghoul. But that's not really the point. Because while he finds that there are plenty of ghouls that happily kill and eat humans at their convenience, there's also a subculture of decent ghouls around the coffee shop Anteiku who help him out and cause as little harm as possible.
For the first ten minutes it's meet-the-cute-characters, everything is sweet and exactly like our world except for the news mentioning ghouls ... and then we have an incredibly bloody tentacle attack by a ghoul. Inevitably Kaneki has a great deal of trouble adjusting to his new status. The wimpy boy's transformation into a dubious anti-hero is a little tough to believe.
The story is mostly about family (the people at the cafe who form his new support group) and morality (ghouls don't have a choice of what they are, is it wrong for them to exist?). What sinks it is weak writing: not much thought went into this. Or at least - there are some weird and wild ideas about ghouls and their bizarro extra appendages (in cheap CG), but getting clever about that doesn't mean that otherwise mundane story-telling is okay.