Themed Harem

A type of Author Appeal in the Harem Genre. Like a particular Moe character type? There's not just one character that fits in this show/game/what have you, but the whole cast is composed of them! (Well, usually. Sometimes there's an odd haremette out, just for variety's sake.)

Necessarily needs something like Four Girl Ensemble or Four-Temperament Ensemble to differentiate their personalities, if not attaching other moe stereotypes to each of the characters, because you can't very well have four or five pining childhood friends that have been waking you up in the morning for fifteen years without a bit of variety between them.

Also, doesn't seem to apply to settings; even though these are actual and well-known moe zokusei, "they're all soldiers" or "they're all schoolgirls" doesn't count, or we'd have every harem series on here and then some. Plus it's really about personality type. If they were all the hardened soldier type with a secret Bodyguard Crush or tall high-school students with inferiority complexes, now that would be different.
Examples:

Originally Eroge and Visual Novels
  • Kanon has four childhood friends; in fact, the fact that Shiori is a standard Ill Girl with no connection to the hero (making her the odd haremette out) may explain why she always gets shafted in adaptations and merchandise. In this case, Nayuki has the traits of the typical Unlucky Childhood Friend, living with the male hero, harbouring a crush on him for years, and losing out.
  • The eroge Little My Maid is Exactly What It Says on the Tin: a meido-centric game (although you could also go after the ojou); the title is actually a pun because it turns out the maids are actually mermaids and, more to the point, the daughters of Urashima Tarō and mistress Hime was his wife, Otohime and is their mother.
  • Lets Meow Meow has 3 catgirls (one of which is a Meido, one is a Robot Girl and the third is a Miko), a rabbit girl, a police officer dog-girl and a Childhood Friend who doesn't mind dressing up like a Cute Monster Girl from time to time.
  • Speaking of trashy Porn Without Plot eroge, Secret Wives Club had Christmas Cake.
  • Futakoi, at the very least, had six sets of twins for the harem. It really took things to the next level and, naturally, repeatedly pushes the protagonist into some sort of awed dizziness (that is, when he's not too busy running from his harem's own "harems" or other "defenders").
  • Sister Princess is Brother-Sister Incest-happy, with 12 or 13 sisters running around proclaiming their Big Brother Attractions. In the game, the legal ones all have optional endings where they turn out to be Not Blood Siblings, and in the anime, one isn't even adopted and is only posing as their sister.
  • Higurashi: When They Cry plays with the trope a little: it only pretends to be a harem series until people start dying, but it's not until that point that it becomes clear that the "harem" has a Yandere/Cute and Psycho theme. There are two odd haremettes out, but both are played up to be crazy before The Reveal.
  • The Visual Novel Katawa Shoujo is set in a school for special needs students, and so all the girls are somehow disabled, ill, or otherwise physically "vulnerable": you get to choose between one who is deaf-mute, one who is blind, one with no arms, one with no legs, and one who is covered in horrible burn scars.note 
  • Dracu-Riot is about vampire girls, with one exception for variety.
  • Imouto Paradise is, unsurprisingly, about Little Sister Heroines. Five, to be specific.

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