World Trigger

A 2013 manga.

One day, an interdimensional gate opened through the skies of Japan. Through the gate, alien creatures initiate their invasion of Earth. However, before they could go any further, the aliens were repelled by a group of humans of mysterious origins. They become known as "Border".

Four years later, a teenage boy known as Kuga Yuuma reached the city of Mikadoshi, where the aliens entered and continued to try to enter Earth. He says he is foreign, but his lack of common sense and social skills hints at his true identity: Kuma is an alien, and his family came from the other side of the same gate the invader aliens came from.

The story also focuses on Mikumo, a high-school student who is also a member of "Border", which fights the aliens with the help of an Applied Phlebotinum known as "Triggers".

Written by Daisuke Ashihara. Published on Shueisha's Weekly Shounen Jump from February 2013 to November 2018, and from then on Shueisha's Jump Square.

Tropes used in World Trigger include:
  • Badass Grandpa: Viza seems very old but has a lot of experience in battle and can perfectly keep up with the younger guys.
  • Bifauxnen: Obishima is so boyish-looking that Kuga mistakes her for a boy.
  • Brother-Sister Incest: Parodied when Shiori creates a fictional storyline for her mole molds where one is the sister of another.
  • Combat Clairvoyance: Jin can see the future, but the way it works it's more like "calculating probabilities", with him mentioning several different futures that are less or more favorable.
  • Eyes Always Shut: Viza never opens his eyes.
  • Gonk: Motokichi is drawn in a very cartoonish style.
  • Heroic Albino: Kuga has white skin and hair.
  • Jerkass: Enedra has no redeeming qualities, he spends all his time belittling and mocking earthlings and boasting about how he is superior.
  • Life Energy: Trion is a biological energy in humans and Neighbors. The Trion Gland produces it and determines a person's Trion Levels. This energy gives power to Triggers, and their output is determined by the quality of a person's Trion.
  • She's Got Legs: The most Fanservice this series gets are Kirie's legs, and those are pretty legs.
  • Surprise Incest: Shiori treats her mole mods like they're part of a Henshin Hero show, and one of these elements she includes is the Pink one being in love with the Black one, not knowing he is her brother.