Sitting perched nearby with a sniper rifle is a fiery young woman named Yuri who introduces him to the world of the not-yet-dead, and offers him enlistment in her armed forces fighting against God and his Angel, a white-haired young woman standing innocently in the middle of a sports field. Yuri tells him to go die, then explains that she's joking; not because she isn't mad at him, but because it is impossible to die in this world. Unamused by what he believes to be her pranks, Otonashi instead walks down and confronts Angel in the field. He doesn't believe that she's an angel and she confirms his suspicions, but when he insists that he can die in this world she strongly rebukes him by conjuring a blade on her wrist and running it straight through his chest. This will not be the last time that Otonashi suffers a theoretically mortal blow in the first episode.
Angel Beats sets up one of its central theses in these opening moments, before you've even had a chance to orient yourself. That is, that a human life is a long series of pains and traumas, some avoidable through proper diligence but most inflicted by the sheer act of living. Every one of the named characters ended up here through death, literally life's ultimate trauma, but more significantly they are all implied to have suffered a horrible trauma in living that rendered them unable to move on past this purgatory. The tragic backstories we are given lean heavily into melodrama but often touch on central societal issues in Japan: alcoholism, domestic violence, poverty, and the difficulties young people face in finding purpose. Nobody here had lived a completely happy life, and they are fighting against a God they view as unjust for subjecting them to such misery.
Despite the heavy subject matter, this is one of the goofier, funnier shows I've watched. There's an entire episode dedicated to a sort of dungeon crawl, where characters "die" in increasingly silly fashions while attempting to get to the bottom of a hidden area beneath the school. It reminded me a lot of the "get to school on time" episode of Kill La Kill, with all sorts of idiotic traps and tearful goodbye speeches that will mean nothing by the end of the episode. It sits nicely next to other great works in the genre, like Defending Your Life or the seasons of The Good Place that focused more on laughs than grand philosophic gestures.
It is very difficult to balance the tonal landscape of a show like Angel Beats, but the creators did a more than admirable job. I absolutely loved this show, and I still think about its best moments more than a year after I finished the series. It's got a really, really wonderful soundtrack and a refreshing positivity for an anime from an era with lots of clunky downers like Death Note and Code Geass. It's an extremely brisk watch once you get a couple episodes in and have a feel for the tone and pacing, and I highly recommend it.