When your favorite characters make you fear for their well-being.
Do you sometimes watch a series and feel like there's no actual danger? Even though the journey is entertaining, you still think that you already know where this is going. Most of the time you can understand which characters are the main ones or crucial for the story, and you feel safe even if it looks like they are about to die. How many of you didn't actually buy Eren's "death" in the fifth episode of Attack on Titan (Shingeki no Kyojin)? But this is not the case with all the shows.
This trick is usually used to keep the audience entertained and not feel safe. If something is too predictable, it's quite easy to become bored after some time. Of course, we're not talking about romance anime, but the ones about war or survival are highly dependent on the feeling of fear. The viewers must know that the stakes are high, this is exactly what makes a series engaging.
Chainsaw Man is a good example of everything we've just talked about. This series has always been known for its shock factor. We don't want to spoil anything for the anime onlys, but let's just say that manga readers promise a lot of heartbreaks in the future.
Akame ga Kill! is also a show that's known for countless deaths. An anime that has the word "kill" in its title was bound to have this trait. Numerous side characters are introduced to the story only for the sake of being killed later, and most of the main characters end up either dead, losing everything or gravely injured.
What about losing a character in almost every episode of the series? If that sounds interesting to you, you should definitely watch Another. This horror thriller not only gets rid of its characters at an alarming pace, but also does it in a gory and brutal way.
Deadman Wonderland anime doesn't cover all parts of its original source material, so the adaptation may not seem as cruel as the manga. Fans say that at least four more characters meet their horrible demise in addition to the ones who were shown in the anime.
It's always nice to actually care for characters and worry about their possible death, it makes the audience more involved in the story, and keeps them on the edge of their seat. However, there always should be balance, so if this trick is executed too frequently, viewers might stop caring altogether, and no one wants that.