From Evangelion
To give a rough demonstration you can roughly split the show into three distinct arcs, and in all of them the world and the tone of the show strongly reflect Shinji's personal internal situation. At first he's thrown into this unfamiliar cold situation where everyone expects things from him. He's feeling overwhelmed, pressured and insecure, so the entire show and the plot take on those qualities. Then as Shinji grows more confident, Asuka appears and introduces a more energetic atmosphere to the show, turning more episodic and silly as well as allowing the pubescent Shinji some room for sexual self-discovery and also open up to others. And then after [Eva] Shinji's experiences in Leliel Shinji is left feeling very unsettled and lost, and shortly after [Eva] is forced to kill Toji which pushes him completely into threatened and traumatized territory. The show from here on turns much more threatening and immediately dangerous, and Shinji deteriorates more and more until both he as well as the story and world approach their conclusion.
Angels are other lifeforms that existed before humans but are genetically similar and act as a kind of cleansing for the apocalypse to restart life. When they appear it's called an impact.
Humans found old angels and reversed engineered them to fight the Angel's off (no idea why Teens are used, other they may have made contact/survived an angel)
Nerv is the organisation trying to fight them Seele is some clandestine front that pretends to try and protect Humanity but really believe the Angels are the rightful inherited of Earth and want them to destroy everything.
Rei is a clone of Shinji mother, created with his fathers help Gendo leader of Nerv so that he could somehow resurrect her properly by gaining the power of creation.
At the end of the Movie Shinji essentially becomes god and everyone is almost in their own personal "heaven", but I suspect with the knowledge they can choose to go back to Earth. That red goo on the beach is essentially humanity congealed together. Ultimately Shinji and Asuka decide to go back to Earth post apocalypse. Might be an Adam and Eve reference.
Caption this Meme
