The series is set 20 Minutes into the Future. Humanity has been attacked and almost wiped out by giant magitech mechas from another universe, which appear through portals on landmasses above a certain size. The only known survivors live on floating structures called Mega Floats. Humanity's only defense against the invaders are personalized superweapons called Heart Hybrid Gears (HHGs). The story follows Kizuna Hida, a high school student who possesses the Heart Hybrid Gear Eros. His HHG gives him the power to recharge other HHG users' power levels by doing lewd things with them... much to his chagrin when he finds out.
The manga ran for 28 chapters in Kadokawa Shoten's Comp Ace magazine from 26 June 2015 to 25 January 2018. It is available in English from Yen Press.
Due to other versions featuring sexual content involving an underaged character in violation of the wiki Content Policy, a decision
has been made to trope only this IP's manga adaptation. You have been warned.
- Aliens Speaking English: Communication problems never show up in this series, not even between people who live in different dimensions.
- And the Adventure Continues: The manga adaptation only covers the first three light novel volumes. After Kizuna defeats Grabel, it ends with an original scene of Kizuna having an orgy with his harem to power them up, then they prepare for the next attack.
- Battle Harem: This series is a World of Action Girls, and most of those girls ultimately fall in love with the main character.
- Bigger Is Better: The Heart Hybrid Gear of a Physical God is over twice as big as a normal one, and several times more powerful. The HHG that goes through the Next Tier Power-Up also becomes much bigger.
- Brains and Bondage(?): When Yurishia first enters the Love Room, it changed to an S&M style play room and changed her attire to black latex bondage wear. Though initially surprised by the sudden change, Yurishia quickly adapts to it and licks her lips in anticipation.
- Cast from Hit Points: All Hybrid Gears work off the wearer's life energy, but the "-ros" series can actually kill the user if its power runs out.
- City on the Water: The Mega Floats, which are technically a conglomeration of floating cities that house the remaining survivors of the invaders' initial attacks. Being a floating city also serves a defensive purpose, as the inter-dimensional gates (or "Entrances") that the aforementioned invaders come from can only appear on solid landmasses (at least the size of a large island) and not over water.
- Clothing Damage: The female members of the Amaterasu Team endure these whenever they take a beating from the invaders when their Hybrid Count is dangerously low.
- Curb-Stomp Battle: Whenever Kizuna is able to go all-out using Eros' full power, returning the favor to Grabel and completely turning the tables against Zelshione until his power fails when his chest piece breaks. Thankfully, Aine is able to step in with her own special ability to take out Zelshione and the entire Batlantis force with Code Breaker.
- Deus Sex Machina: Kizuna and his Eros Hybrid Gear can perform the normal "Heart Hybrid" and the more intense "Climax Hybrid" with Aine, Hayuru or Yurishia. Heart Hybrid restores Hybrid Count, while Climax Hybrid allows access to a Super Mode. Taken to high levels of Refuge in Audacity with the "Connective Hybrid." Eventually bypassed altogether with The Power of Love in the anime adaptation, implying the sexual activity is merely a stepping stone to it.
- Ecchi: This is a series where the main character and the girls in his harem actually get stronger when they get to third base. Saying there is Fanservice here is like saying the ocean is wet.
- Elaborate University High: The Strategic Defense Academy Ataraxia, which doubles as a Military Academy, research center and the Japan Mega Float's first line of defense against the invaders.
- The Empire: The Batlantis/Vatlantis Empire, better known as the invaders from another universe. Aldea implies that their empire spans half of the world in their dimension.
- Excuse Plot: Downplayed. The series does have a legitimate plot separated from all the Not-Quite-Sex scenes, but it's undeniable that many plot points in the series exist entirely to justify the usage of Deus Sex Machina.
- The Immodest Orgasm: This usually happens to Aine, Hayuru or Yurishia after a successful Heart Hybrid or Climax Hybrid.
- Magitek: Spelled "magitech" but otherwise pretty standard for both sides. The Heart Hybrid Gear technology, which also doubles as Powered Armor, is implied to run on the user's Life Energy (a.k.a. Hybrid Count). When it reaches dangerously low levels, the armor disappears. And for the "-ros" series, once the Hybrid Count reaches zero, the user dies. So far, only Kizuna has the ability to replenish the Hybrid Count of his Battle Harem... by doing indecent acts with them.
- Mecha-Mooks: Most of the magitech weaponry fielded by the invaders are this.
- Mundane Utility: For a given value of "mundane". The simulation technology used in the "Love Room" was originally developed for combat training, but instead it was used to simulate romantic scenarios to help in the Heart Hybrid sessions.
- Nipple and Dimed: The light novel illustrations never showed the nipples of the girls. Not so with this manga: even when fully clothed, the girls are consistently drawn with pokies.
- Not What It Looks Like: Twice in chapter 2. First Chidorigafuchi breaks into Kizuna's bedroom to get him to perform Heart Hybrid with her again, only for Himekawa to come in looking for Kizuna and catch them in flagrante delicto. Then the entire student body at their school is shown video of the process from the previous battle, and concludes that the whole Heart Hybrid thing is just an excuse for Kizuna to grope girls, despite the main cast insisting the contrary.
- Stripperific: The pilot suits that the main cast uses. As a case of In-Universe Values Dissonance, the clothes that the people from the Batlantis Empire casually wear are not what most people from "Lemuria" would consider appropriate for a stroll in the city.
- Super Mode: Aine, Hayuru and Yurishia can access a so-called "Immoral Weapon" by getting their Hybrid Count above full. And the only way to do that is for Kizuna and any of the girls to perform a more intense version of Heart Hybrid, that is, Climax Hybrid. This procedure also powers up Eros, making it more useful in combat.
- Super Multi-Purpose Room: What the "Love Room" amounts to. It is capable of recreating any situation or scenario, ranging from battle simulations to dating spots and hotels and can even change what people are wearing. Its main purpose is to ensure things go smoothly between Kizuna and the girls.
- Technical Virgin: Kizuna and his Battle Harem. They engage in several different sexual acts during the course of the series, but they never have penetrative sex.
- Theme Naming: The "-ros" series of Heart Hybrid Gears: Aine's Zeros, Hayuru's Neros, Yurishia's Cross/Kuros, and Kizuna's Eros.
- Translation Convention: Silvia, Yurishia and the other Masters may have learnt Japanese before coming to Ataraxia, but there is no reason for them to still be speaking that language when they are speaking among themselves. The most obvious example would be the footage of one of Masters' missions back when they were still in America that Kizuna found. The dialogue is still presented in Japanese, even though they are obviously speaking English.
- Vision Quest: Each of the Heart Gears has to increase their bond with Kizuna during Climax Hybrid sessions. The "Love Room" is designed to expedite the process by projecting holographic clothing and scenery based on each girl's inner kink to increase their sexual arousal, since Climax Hybrid can only be achieved when they accept themselves for who they are.
- World of Action Girls: Naturally, being a Battle Harem series where the Chick Magnet hero is the only named male character.
- World of Buxom: With the notable exception of Sylvia, who is eleven, all the girls are quite stacked.
