How many harem titles you have consumed over the course of your anime hobby is likely to determine how funny you find this book. I Saved Too Many Girls and Caused the Apocalypse is a straight send-up of the genre, and while it also adheres to a lot of the conventions it's lampooning, it manages to be so over-the-top ridiculous in places that most of the genre-weariness that readers may be suffering gets eliminated. It isn't a perfect satire, but it hits enough right notes that it can be truly funny.

The story immediately throws three separate harem plotlines at us in a series of prologues – one for each of the heroines and one for the hero. First up is Satsuki, the hero's childhood friend. Her family of mages carries the power to access a powerful spell, and the first man Satsuki kisses once she turns sixteen will become her life partner and have equal access to those powers. Since it could be just as easily used for harm as good, a nasty mage with the delightfully ludicrous name of Messiah Kyandistrap plans to claim Satsuki as his own. The only way out that she can think of is to get childhood buddy Rekka to kiss her first on their mutual birthday. Then there's Iris Fineritas Cyphercall, a princess from the planet Fineritas whose father wants her to marry a repulsive intergalactic tyrant. Iris flees to Earth in her spaceship where she runs into Rekka, falls for him instantly, and asks him to help put a stop to the engagement. Finally, Harissa Hope is a young summoning mage who's her kingdom's Last Hope in a parallel world, tasked with summoning a hero from another world – Rekka, of course – to defeat the demon king

Even one of these stories would have been too much for Rekka. He likes to fly under the radar, and his father's news about his savior bloodline is not welcome. At the same time, he's a nice guy, and while he'd like to just be left alone, he also recognizes that he's their actual Last Hope . He does come close to just leaving Harissa's story, and he actively tries to get out of Iris's, both in order to go back and help Satsuki. This makes sense, since she's the only one he's known his entire life. But reluctant or not, he is a harem protagonist, and he's obliged to aid the ladies.

Of course, we can see how this is going to get him into the situation that R has come to stop. Like most of his brethren, Rekka is only a nice guy – he doesn't actually have much interest in doing anything romantic with his harem. There are several situations where Rekka could have solved R's problem by kissing one of the girls, but his own reticence and cluelessness prevents it. This is part of the humor, but it's perhaps the least effective gag simply by virtue of following so closely to genre convention. Where the book shines is when Rekka tries to resolve all three plotlines by borrowing skills, items, and conventions from the others. The best scene is undoubtedly when Rekka bypasses the whole party-assemblage and pulling-the-sword-from-the-stone bit in Harissa's tale to simply blast the hell out of the demon lord with a laser gun from Iris' spaceship. It's also indicative of the way Rekka borrows from each plot to resolve the others, although nothing else quite lives up to it in terms of humor or bizarreness.

As a protagonist, Rekka is remarkably not annoying, possibly because we're in his point of view and he's genuinely irritated and confused by the whole situation. Of the girls, Iris and R are the biggest offenders, although Iris is admittedly the pushy ojou-sama/tsundere type I personally find annoying, so your mileage is likely to vary. R, on the other hand, comes off as smug and deliberately antagonistic, which seems at odds with her mission to prevent the War of All that Rekka's indecisiveness will eventually cause. At the end of the book, we do have to wonder at her actual motives, as she makes a comment that sounds as if she considers herself part of his destined-to-expand harem. Could she simply be here to try to get a head start on other competitors?

That will have to wait until later books in the series, which is ongoing in Japan with seventeen volumes as of this writing. Whether or not the author can keep up the humor for that long, or even for another volume with the presumed addition of more girls, remains to be seen, but the harem genre certainly offers enough possibilities for satire – demons, angels, goddesses, cat-girls, monster girls – Namekoujirushi comes up with plenty of fodder, and Nao Watanuki does a nice enough job at creating art that's generic yet pleasing to the eye, like any cookie cutter harem series.