Katawa Shoujo/Nightmare Fuel


 * Hisao Nakai suffers from a heart defect diagnosed as arrhythmia that, at any moment, can kill him if he's not careful to take his pills and not overexert himself. When his heart starts to act up, it is accompanied in game by a prominent Heartbeat Soundtrack and red vein-y borders around the edges of the screen. It's frightening enough to almost convince you you're about to have a heart attack...
 * Oh, how sweet! His crush is about to admit her feelings for him!.