Darling in the Franxx

Darling in the Franxx (Japanese: ダーリン・イン・ザ・フランキス Hepburn: Dārin In Za Furankisu), abbreviated as DarliFra (ダリフラ DariFura), is a 2018 Japanese science fiction and romance TV series in 24 episodes, produced by CloverWorks and animated by Studio Trigger, that ran from January to July 2018. Crunchyroll and Aniplus Asia simulcasted the series, then Funimation dubbed it in English. There are also two manga adaptations, one by Kentaro Yabuki from To Love Ru.

From this day forward, you are now my darling!~

The series happens in a dystopian future, where adults and children live separately. The adults are immortal and live in the cities normally, but they don't pursue relationships and don't have kids. Children and teenagers are artificially born/created, ahve shortened lifespans and are referred to as Parasites, raised solely to pilot the gigantic mechas named Franxx in male-female pairs (with guys known as "stamens" and girls called "pistils"), and are otherwise treated as expendable pawns by the leaders of humanity, an Omniscient Council of Vagueness known as APE, which is led by the mysterious "Papa". So, other than having to fight the evil and gigantic aliens known as the Klaxosaurs, these children and teens have next to no actual purpose and hope for the future.

One of the many Parasite teams is Squad 13 of Plantation 13. Hiro is one of the kids in that group: once believed to be a Child Prodigy, he's now a depressed teen unable to connect with his partner Naomi, and therefore neither of them cannot complete their training and she dies. However, Hiro's luck is about to change: he finds a new partner of sorts in Zero-Two, a horned girl called "Partner Killer" since all of the "stamens" who have worked with her died after their third joined battle. When she loses her current stamen, Hiro becomes her "darling" AND survives the three following battles. Soon, both of them plus Hiro's remaining companions (Ichigo, Goro, Mitsuru, Kokoro, Ikuno, Futoshi, Miku and Zorome) begin their shared Coming of Age Story, fighting the klaxosaurs together and starting to question the world around them little by little...

Tropes used in Darling in the Franxx include:

And Now for Someone Completely Different: Episode 7 is narrated by Ichigo instead of Hiro like previous episodes.
As You Know: In Episode 3, Hachi explains the method the kids must use to defeat the klaxosaurs in this way.
Beam-O-War: Zero Two's mecha engages in one with a Klaxosaur in Episode 1. It loses badly, to the point of being sent flying back, but the creature is also stunned temporarily.
Beach Episode: In Episode 7, Squad 13 is given a vacation on a beach as reward for defeating the Klaxosaur in the previous episode.
Curb Stomp Battle: Episode 1. Once Hiro joins Zero Two, Strelizia manages to easily dispose of the giant lizard-like klaxosaur.
Fanservice: As far as the eye can see. There's a lot of scenes in girls in their underwear, Zero Two is Going Commando in the first opening, etcetera etcetera. Isn't very surprising the manga adaptation was given to the same artist of To Love Ru.
Implausible Deniability: In Episode 4, Hiro and Zero Two come to the control room in their battle uniforms. Nana says they can't go and wearing the uniforms will not change her decision. Zero Two says she didn't say anything, that is technically correct, but it's hilariously obvious how she wanted to fight.
Loophole Abuse: In Episode 3, Hiro can't cross an barrier inside the base because he isn't allowed because of his status, but Zero Two can. She solves this by making Hiro cross the barrier along with her, touching her body.
Mechanical Lifeforms: The klaxosaurs resemble machines, and sound like them.
Theme Naming: Parasites generally have two-digit codes. The fact Zero Two only has one is already an in-universe signal she is abnormal.
You Are Number Six: Parasites don't have proper names, rather they have codes. This didn't stop Squad 13 of naming themselves according to the kanjis of the numbers. By example, 015 is Ichi(1)go(5).