While Haibane Renmei couldn't be more dissimilar, the concept of the characters being in a supposed afterlife or purgatory are both extremely integral to the setting. Although in Angel Beats!, it seems like they fear the next step and thus rebel in anyway to ensure they don't disappear. However, in Haibane Renmei, they do the exact opposite and are more resigned to their fate, and there is little conflict.
Similar premise, very different execution.. Haibane takes away the comedy, action and some cuteness factor in order to bring more deepness to the premise setting, but both anime can leave you wondering the same questions about life purpose, and death.
Similar in both is by accepting yourself(regret) or atone your sin of your past before death you will be free from that world. Born to other world where they had to do work and live on with other people a.k.a citizen of that world.
In both, people are born into another world after they die because of regrets from their life before and stuck there until they can get rid of their regrets and become at peace with themselves.
Angel Beats! and Haibane Renmei have similar concepts, as both are centered around characters who are in a purgatory-like setting. While Angel Beats! has more comedy and action, Haibane Renmei takes a much more serious tone, and also likes to leave things up to the viewer to interpret. Liking one of these shows does not necessarily mean you will like the other, but it is worth trying.
Imagine having found yourself, to an unknown world, as if a lucid daydream not to be awakened. The rejection and self-denial is nigh, as the individuals, Yuzuru and Rekka, slowly identify with their pasts and gradually accept the truth, within the labyrinth of both worlds, the "afterworld", and the real world. Haibane Renmei, an astute yet nostalgic series that carries an abstract, yet distinct air of suspense to it; Angel Beats, a fulfilling adventure in an alternative (afterlife) world to slowly depreciate and disintegrate as reality steps in. Both attempt to carry a complete and touching plot, with a natural flow in Haibane Renmei; while
Both stories take place in an after life of some sort and has simmilar themes.
Haibane Renmei is more serious then Angel Beats, though.
Both anime explore the concept of "Afterlife", and features the characters being trapped in another world due to their regrets from their past lives. Both characters are required to find peace within themselves to be finally set free.
Haibane Renmei is much more serious and complex, while Angel Beats! is a lot more comedic and action-packed.
+ Different interpretations of the afterlife for a group of people who appear to be adolescents despite not being human
+ The wall in Haibane Renmei is similar to how the world just ends outside of the high school in Angel Beats!
- Angel Beats has action and much more vivid animation (granted it is 8 years younger) than Haibane Renmei which has a much calmer yet eerie atmosphere throughout the show
Haibane Renmei has been renowned as "Angel Beats for Hipsters" due to having more philosophical approach, classic western settings, symbolism, and less comedy/action/moe.
Both are stories about little children that have to accept their conditions and moving on from their past life sins/regrets in afterlife settiings.
Watch Haibane Renmei A F T E R Angel Beats.
You'll see a TRUE sad anime, and not a random tear-jerker.
Although Angel Beats! and Haibane Renmei each possess a different atmosphere and overall feel, they both share a similar setting and the theme of people moving on to the next life.
Both shows start off with the main character (Otonashi in Angel Beats! and Rakka in Haibane Remnei) awaking unsure of their past and where they are. Throughout the series, the protagonists learn about the true nature of the worlds they inhabit and that they have moved on to a new life. Also, both of these anime end on a sad note, but Haibane Renmei's ending is more welcome and hopeful than Angel Beats!'s