Berserk opens up with this Black Swordsman character named Guts, and his goal towards killing the demonic beings called Apostles. Obviously he has a history with these creatures and the narrative goes into that.

Sarasa is the protagonist of the story, and while the first part starts off slow, towards the ends when Sarasa's village is destroyed and her twin brother is killed, it is up to Sarasa to stand in for her brother and lead her people.

What can I say, as Rumiko's best work, I liked how the characters and the humor did a good job of hooking me for the story.

It becomes pretty clear that there are supernatural elements in Blue Exorcist, and that Rin has a connection to these supernatural beings, though that's revealed in the middle of the chapter.

The first more or less introduces Clare as the protagonist, when she is forced to kill someone's family who has become a Yoma. And to get an idea of how Claymores fight in the series.

The first chapter more or less shows how Kaoru and Kenshin meet at the beginning of the series, and how helping her out and then staying continues to have an influence on the series, since he has quite the history as the manslayer.

Mostly is focused on developing the world building of Akira and how Tetsuo's encounter with the test subject has an effect on the story.

We see how Sena slowly begins to become his own person when he is introduced to Hiruma's football club.

Shows a bit of Battle Royale's world building and introduces each major character before they are forced into the Battle Royale game.

It feels pretty awesome how a teen like Ichigo gets roped into the world of Soul Reapers the night he meets Rukia. But everything really escalates when a hollow attacks his family and he has to take matters into his own hands. Its true that Bleach lost itself after the first two arcs, but there was some incredible build up during those two arcs.