Once a prince of the Arcadia empire, now a Drag-Ride user with a penchant for peeking on half naked girls, Lux is Saijaku Muhai no Bahamut's lucky harem lead. After a particularly troublesome incident in the Royal Knight Academy's women's baths, Lux is challenged by the princess of the new kingdom, Lisesharte Atismata, to a duel, with the promise of a place at the academy on the line and basically no other choice. So with a new school life looking likely, as well as a harem of cute girls forming around him, things are about to change for Lux, "The Weakest Undefeated".

Just like Infinite Stratos, Saijaku Muhai no Bahamut features a distressed male protagonist placed into a girls only school, with Bahamut's Drag-Ride users being almost entirely female. The Drag-Rides themselves are pretty much IS Units, so the action in Saijaku Muhai no Bahamut feels very similar as well. One of the standout differences between the two is the setting, with Bahamut taking place in an old looking fantasy world, as opposed to the futuristic world of Infinite Stratos, however, the feeling of both shows remains very much the same. If you want the same ecchi, action, and cute girls that Infinite Stratos provided, then Saijaku Muhai no Bahamut should be right up your alley.

With the planet under attack by aliens named Savage, it was necessary for humanity to create a weapon capable of fighting them. Introducing the Hundred, a technology that provides its user with weaponry suited to their own combat style, and enabling them to fight against the invaders. Hayato Kisaragi is one of the newest recruits at Little Garden, an academy where Hundred users, known as Slayers, are trained. Managing to start off his new high school life by dueling the school's Queen, Hayato proves that his Hundred packs quite a punch, and as you expect can look forward to many more exhilarating fights and beautiful girls in the near future.

Much like Saijaku Muhai no Bahamut, Hundred is another show that starts off in a fashion disturbingly similar to Infinite Stratos, with the story becoming its own as time goes on. Hundred features the IS Units we're all familiar with, though now called "Hundred" and with a wider variety of abilities and weaponry. So as you can imagine the action also remains very similar, with aerial combat, big guns, laser swords, and just about everything exploding. You'll be happy to know the fan service is quite abundant as well, with a harem of cute girls always about, including the strict student council president, adorable idol, and a childhood friend of questionable gender. So if you liked Infinite Stratos, then Hundred is definitely one you'll want to add to your watch list.

For the past thirty years, the world has been ravaged by a new kind of natural disaster: explosions known as Spacequakes that occur randomly and kill millions almost instantly. These Spacequakes signal the arrival of beings known as Spirits, powerful and beautiful girls from another world. Despite the best efforts of the anti-Spirit squad, and the defensive measures being put in place, it seems that nothing can be done to put a stop to the continued arrivals of said Spirits. Caught in the latest such arrival is Shidou Itsuka, who is lucky enough to meet the adorable, if destructive, Spirit code named "Princess". Shidou, however, decides to take a different approach to the gun-toting anti-Spirit Squad, realising that the Spirits can also be subdued by falling in love.

Date A Live is the only series you'll see on this list that doesn't actually feature a battle school or academy, which seems to have become a commonplace theme in recent years. So what makes it similar to Infinite Stratos? Well, it does have power suits similar to the IS Units, aerial battles, cute girls, and ample fan service, so the two certainly share a lot of the same themes. On the other hand with the plot centered around saving Spirits, mixed with slice-of-life date episodes, the overall feel of the series is a bit different, with it being more centered on the girls themselves than anything else. If you want a series that steps away from school and is frankly pretty whacky, then we'd recommend Date A Live.

Heart Hybrid Gear: an ability which allows the user to fight against invaders from another world, and Hida Kizuna is one of the few capable of wielding it. Though not exactly powerful by himself, Kizuna has a special ability that has made training him at the Tactical Defense Academy Ataraxia worthwhile. Yes, he can power up other Heart Hybrid Gear users through perverse and erotic acts, something which only he can do. Fortunately, the top three girls at Ataraxia are not only real beauties but have already taken a liking to Kizuna. Cut to skin tight flight suits and borderline hentai.

Masou Gakuen HxH is like Infinite Stratos cranked up to ten, requiring separate uncensored episodes to fully divulge its lewd contents. So if it was ecchi and fanservice that brought you to Infinite Stratos then look no further, because HxH has it by the bucketful. The power suit battles are there as well, so you can expect similar content as far as action goes, although we'd say that Infinite Stratos focuses more on the fighting aspect, and HxH more on...powering up the suits. If you can imagine a hentai artist deciding to make his own Infinite Stratos spin-off where everyone has even bigger chests, then that's Masou Gakuen HxH in a nutshell.

Kamito Kazehaya is the most unusual new student at Areishia Spirit Academy, an academy intended for shrine princesses. As the first man in 1000 years to be capable of contracting a spirit, he finds himself attending the prestigious girls academy, designed to train its students in how to fight using their contracted spirits. Not only that, but he's being forced to participate in the upcoming Blade Dance tournament, which for various reasons he's not exactly looking forward to. Managing to spend his first day pissing off fiery tsundere Claire Rouge by seeing her naked, as well as "stealing" her spirit, Kamito is not off to a good start by any means.

Once again we come across the "only guy at a girls school" scenario which means you can expect constant fan service and a cast made up almost entirely of cute girls. Seirei Tsukai no Blade Dance is another series that does pretty much what it says on the tin, with some romance, ecchi, magic battles, and a good enough plot to hold everything together. But although the themes in Blade Dance and Infinite Stratos are very similar, the settings are very different, with Blade Dance set in a fantasy world of spirits and magic. So if you liked Infinite Stratos but fancied a change of scenery, why not give Seirei Tsukai no Blade Dance a try.

After an incredible disaster shook the planet, the emergence of special humans with remarkable abilities known as Genestella began. Ayato Amagiri has just started his high school life at the Seidoukan Academy, one of the top six schools in the world that trains Genestella students to use and control their powers. Peeking on princesses, meeting old friends, and saving damsels all appear to be talents of his, with Ayato and his new friends going as far as to compete in the next Pheonix Festival, a battle between schools. But ignoring all of that, Ayato actually has a different and darker reason for joining Seidoukan Academy in the first place.

Primarily an action series, Gakusen Toshi Asterisk focuses heavily on battles between students using a combination of futuristic weaponry and modernised magic. Although certainly fanservice heavy, Asterisk's ecchi moments are more few and far between than in Infinite Stratos, with the cute girls serving more as eye candy between fights. With a pretty awesome soundtrack and great visuals during action scenes, Gakusen Toshi Asterisk gets pretty hype and is the kind of show that you can easily marathon. So if you want something action-packed and fan service heavy but perhaps with a little less mecha, then definitely give Gakusen Toshi Asterisk a shot.