Fatal Hearts

Fatal Hearts is a visual novel from Hanako Games, an independent American group of small time game makers. It is a heartrendingly sad and romantic coming of age story about Christina, a bored teenager wasting her summer with her friend Lucy. When young women begin to turn up murdered in abandoned areas, and Christina happens across one of them, her life is changed forever as she is drawn into a strange world of vampire cults and werewolf clans. If the player makes the right choices, Christina can pair up with (almost) anyone, but if you play your hand wrong, you might just be killed by your former allies.

Crazy cultists, immortal vampires, cuddly (or deadly) werewolves, and it's way too easy to kill off your character. Seriously.

Tropes used in Fatal Hearts include:

All There in the Manual: Some of the puzzles have no background information for them, which the manual/gameguide gives. Also, the 'secrets' section at the end reveals how Sebastien became a vampire and who Christina and Katie really are.
Badass Normal: Jeremy.
- He's neither a vampire nor a werewolf, but he doesn't quite count as normal...
Fur Against Fang:
Gay Option: Lucy
Grid Puzzle: Box of Runes puzzle.
Japanese Vampire: Sebastien
Magic Square Puzzle: One of the puzzles, complete with fun history lesson (tm).
Nintendo Hard: Some of the puzzles do not have useful clues to them, and rely on the player randomly button mashing until they get the right answer.
Our Werewolves Are Different: Anyone can become a werewolf by wearing a special belt and becoming in tune with their inner spirit. Though, honestly, they tend to look like pet dogs...
Poor Communication Kills: Unfortunately, that would be you.
Right Hand Versus Left Hand: To some extent. Of course, blood grudges and bloody fanaticism are also to blame. Two endings have you bringing both sides of the conflict together in peace.
Three Plus Five Make Four: One puzzle has you doing this with flour. You need 2/3 cup, and you only have an 800ml cup and a 300ml cup. I hope you're good at converting...
Vampire-Werewolf Love Triangle: Particularly on Tim's path, where it may end badly.