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Manga / School Mermaid

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A horror manga / anthology series by Akihito Yoshitomi (author of Blue Drop and Eat-Man) about Japanese school girls who really want boyfriends. But rather than going through the trouble of getting the attention of a boy, talking to them and just being themselves, they decide on a much quicker way to do so... By hunting mermaids in their school and eating their flesh.

No, really. That's the premise.

Around a few Japanese high schools, an old worn out notebook is passed around detailing a certain spell that, when chanted at a certain time at night, will cause human looking mermaids to appear before the user. These mermaids wear school swimsuits with a letter on their chest. If the mermaid with the first letter of the name of the boy you love is caught and killed, all you have to do is eat the flesh of it while thinking of your true love and, presto, instant boyfriend. However the mermaids won't be caught so easily since they can swim through the walls and floors like water and are extremely fast to boot.

This doesn't deter the girls who find this notebook and indeed give it a shot. The thing is though some are quite, er, competitive in trying to get what they want. And then of course there's the much deeper dark secret of the mermaids themselves.

Originally published as a three-chapter one shot story, it was given a short serialization run in Champion RED in 2006 that managed to produce two volumes of material. That was thought to be the end of it. But in 2016, the series was granted a second serialization run, under the title School Mermaid 2 continuing the story with more added twists to the mermaids. Unlike the first series though, the second has a more central protagonist and connected storyline.


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  • And I Must Scream: In an interesting sense, in the last story one of the characters surmises that the reason the mermaids will sometimes go on the attack is that they can feel if someone who enacted the spell truly does love a boy and doesn't need the flesh of a mermaid to get him to return their feelings. As such they become jealous of that person and try to kill them because they know they're stuck by the spell's curse and can never have that kind of affection because they tried to take the easy way out through the spell rather than simply come out with their feelings. This might be why they're constantly smiling for potential victims, they're not really genuine as if they're hoping for their pursers to fail. In fact, a sign they're about to turn feral is when they don't do this, meaning they sense a girl's true affection for a boy.
  • Author Appeal: There's only one reason behind the mermaids being portrayed as cute (but creepy) teenagers in classic Japanese school swimsuits...
  • Brainwashed:
    • Whatever the spell does to the girls after they turn into mermaids, it strips them of their personality and makes them akin to mindless dolphin like creatures whose only instinct is to try to avoid being killed by their pursuers. A recent tale actually revealed that some of the more prominent personality traits can survive mermaid-ification, especially if a mermaid has a strong connection with a potential pursuer.
    • What happens to the men who are the recipients of the spell. They immediately fall in love with the girl no matter if they were in love with someone before. As Taakaki shows, it twists the man into a shell of himself.
  • Clothing Damage: During mermaid-ification, the clothes they were wearing as humans were explicitly destroyed during the transformation.Naturally, they're naked when after they perform the Blood Bath to become human again.
  • Cute Mute: All the mermaids. Obviously cute, and can only make screech sounds. Subverted, they can talk if only in parrot-like fashion.
  • Dissonant Serenity: The mermaids don't seem the least bit bothered by being stalked by girls trying to kill them, until one gets brought down. Also seen when Haruko watches them drag Yoshiko away.
  • Double Standard: Rape, Sci-Fi: The story takes a long while to explore the Mind Rape of forcing a man to fall in love. Previously it was relegated to the ending and the one time we see the effect on Toshiko and Naomi it's played completely straight. (Though one could argue, their fate is partly karmic.)
  • Fragile Speedster: The mermaids are indeed fast but one heavy blow will take them out instantly.
  • Given Name Reveal: First names tend not to be brought up at first. This helps hide the fate of some to be used as targets of the mermaid curse.
  • I'm a Humanitarian: Anyone who eats mermaid flesh, since mermaids are magically transformed humans. And you must do so, not only to get your wish for whom you want to love you. But if you don't, you get transformed into a mermaid immediately afterwards. Somewhat subverted, as one tale shows that mermaid flesh tastes like fish.
  • Love Makes You Evil: Some of these protagonists really want a boyfriend, to the point they're willing to kill each other if they like the same one.
  • Magic Pants: Inverted. The mermaid transformation explicitly destroys clothing the transformee was wearing as a human and replaces them with the classic Japanese School Swimsuit. Yet, if the mermaid performs the Blood Bath to become human again, the swimsuit doesn't carry over in the reversion, possibly because the swimsuits are actually part of the mermaid transformation spell itself.
  • Naked on Revival: When a mermaid performs a Blood Bath on their beloved and turns back into a human, the transformee reverts back naked, drenched on their beloved's blood. Makes sense because the clothes that they were wearing as humans were destroyed during their mermaid transformation.
  • Nightmare Face: You think those mermaids are just cute bubbly creatures? Some nights they may not be in the mood to be playful, leading to this happening.
  • Our Mermaids Are Different: Most obviously, they look like schoolgirls in swimsuits, able to "swim" through walls like they were water. Though when they go on the attack, they start looking more like the mermaids from old tales i.e their skin becomes more scaly, they gain fins on their hands, their nose disappears and they suddenly sprout fangs.
  • Race Against the Clock: You'd better be finished by the time sun comes up...
  • Sand Is Water: The Mermaids are able to move about through solid surfaces as if they're in water. Making it tough for their pursuers to catch them.
  • Squee: Creepy mermaid sound. In fact, it's all they can say especially when one turns into a mermaid if they don't eat mermaid flesh by sunrise. However, ones that retain some of their mental faculties, like Kaori, are still able to display affection through tactile means.
  • Tome of Eldritch Lore: The Journal detailing the mermaids and how to hunt them. It obviously contains Things Man Was Not Meant to Know.
  • Turning Back Human: It turns out that it is possible for a mermaid to revert back to a human, but they must perform a Blood Bath on the blood of the one they love, killing that person in the process. Doing that isn't perfect though, as the former mermaid will still act like a mermaid. To get this right, they have to eat the flesh of the mermaid whose letter is after theirs.
  • Was Once a Man: The mermaids were actually all human school girls at one point who invoked the spell. They failed to catch a mermaid before sunrise however and the spell turned them into mermaids themselves, doomed to be hunted and eventually killed by the next people who find the notebook.

First Run

     Haruko and Yoshiko (The original one shot story) 
  • And Then John Was a Zombie: Happens to Yoshiko as she was unaware what the price of failing to eat mermaid flesh meant.
  • The Bad Guy Wins: Haruko wins, but the ending brings up the possibility that one day she will screw up and lose in the worst possible way.
  • Batman Gambit: Haruko pulls one on Yoshiko - helped along by the fact that the latter had more than one flaw that fed into it.
  • Downer Ending: Haruko got Yoshiko turned into a mermaid because Yoshiko is easy prey, and Haruko will move on to the next person - boyfriend, victim, somebody. There is the possibility that she will screw up at some point, and get turned into a mermaid herself, though.
  • Evil Plan: Brilliantly masterminded by Haruko on the unathletic, weak-hearted Yoshiko from the beginning.
  • Eviler than Thou: Haruko happily pulls the trigger and eats the mermaid while Yoshiko is going through her Heroic BSoD/ Villainous Breakdown and is doomed by it.
  • Flaw Exploitation: Why Haruko chose to partner up with Yoshiko in the first place. She knew that Yoshiko wouldn't be able to bring herself to kill and eat the mermaid, and so would become one as well. This would get her out of the way and ensure Haruko would then have a weak and easily killable mermaid to hunt the next time she wanted one, since she knew Yoshiko's other flaws would remain after her transformation.
  • Heroic BSoD: Depending on how you view Yoshiko, her loss of composure in the last chapter spells her doom.
  • The Reveal: Once Haruko completes her endgame, Yoshiko experiences first hand why there are mermaids there in the first place.
  • Slasher Smile: That creepy-ass grin of Haruko as Yoshiko is turned into a mermaid. You'll know it when you see it.
  • Unwitting Pawn: Yoshiko can't bring herself to eat Ohara, and that attack of conscience dooms her when Haruko's subsequent Eviler than Thou Batman Gambit comes to fruition.
  • Villain Protagonist: Both girls but Haruko's Eviler than Thou Gambit turns Yoshiko into the hapless victim.

     Toshiko and Naomi 
  • Book Ends: Toshiko's nights with Mermaids begins and ends with being embraced by a girl. For opposite reasons.
  • Chekhov's Gunman: Yuuko, the girl that Toshiko sees turned into a mermaid when she found the book. Ironically, she accidentally kills her when she thought it was Naomi trying to creep up on her.
  • Double Knockout: A magical version of this trope. Both girls cast a love spell on each other for selfish reasons and end up becoming a couple in spite of their mutual hatred.
  • Jerkass: Naomi practically forces herself into Toshiko's mermaid hunt after hearing Naomi likes the same boy she does. What's more she actively hurts Toshiko to get an early lead.
  • Karma Houdini: Despite being a complete and total bitch, Naomi gets away with everything and even gains a lover.
  • Happy Ending: Arguably the most uplifting ending of the entire series, as even the final story ends on Namae still being at large and preying on other girls. Toshiko and Naomi end up happily together, and they don't seem to be traumatized by the event at all. Though the ending still shows the notebook getting passed on to another girl, the way the two lovebirds giddily give it away together is just too damn adorable.
  • Laughing Mad: Toshiko gives one when she decides to make Naomi loves her to save herself.
  • Oh, Crap!: Toshiko gives a very mild one in her head when she realizes that Naomi has also made her her lover in turn.
  • Pair the Suitors: The twist ending. They are after the same boy, but when dawn falls the only mermaid they killed has the wrong name, forcing both of them to cast the spell on each other instead. They instantly transform from hated enemies into a lovey-dovey couple.
  • Spit-Trail Kiss: Toshiko and Naomi's first kiss has a pretty impressive trail between the two. Surprisingly it doesn't have any of the blood that is in their mouths.
  • Unwitting Instigator of Doom: Toshiko and Naomi end up passing the notebook to Ohara. It's unwitting as all hints are that they didn't mean to kill a bunch of people.
  • Yuri Genre: Both Toshiko and Naomi end up like this after consuming the mermaid flesh.

     Misaki and Noriko 
  • Poor Communication Kills: Noriko manages to kill an "M" mermaid which Misaki is able to cut flesh from and eat before Noriko reaches her, thinking that Misaki stole the one she loved from her. Turns out Misaki wanted someone else who had a name with the letter "M". Noriko just assumed she loved the same boy she did. Misaki calls her out on this stating she went crazy on her before she got the chance to explain. If that wasn't bad enough, time runs out before Misaki can share the mermaid flesh with her, causing Noriko to become a mermaid.
  • Teacher/Student Romance: A very disturbing reversal of this it's the teacher who wants the student in this case. The end of the story reveals that Misaki's real plan was to make a middle-aged married teacher fall in love with her... and considering that the mermaids went feral and attacked her, this implies that Misaki's feelings were reciprocated all along.

     Mariko and Kaori 
  • Continuity Nod: Doubles as Fridge Brilliance and Fridge Horror. The transcript of the mermaid spell and the effects of the curse fails to include the information on the page that Haruko kept from Yoshiko about what happens when you fail to eat mermaid flesh before the sun rises once you recite the spell. Makes one wonder if Haruko decided, in her sadistic thought processes, to keep the page out of the journal so future users of the spell had no idea of the consequences...
  • Lighter and Softer: Well, as Lighter and Softer as you can get in a horror anthology manga. The only mermaid killed is done so offscreen, and it reveals several things about the mermaids, such as the fact that the mermaids can retain aspects of their original selves, can interact with objects in the real world, don't actually taste like human flesh, but fish, and can display affection for each other. However, it also reveals that the mermaid spell works outside of the original school...
  • Love Martyr: Kaori loves Mariko despite Mariko ending their friendship and insulting her constantly. She even kills a mermaid so Mariko can be with the one she loves and even after being turned into a mermaid loves her enough to offer her own flesh. Mariko lampshades how Kaori is always looking after her.
  • Poor Communication Kills: Kaori and Mariko begin their tale having found a rough transcript of the original journal's instructions. However, the transcript failed to include several key notes, such as the consequences of what happens when one does not eat mermaid flesh after reciting the curse.
    • Also Kaori didn't need to get a G mermaid for Mariko as the one she cared about was Kaori herself. If Mariko could've explained or confessed her feelings, none of the plot would have happened
  • Surprisingly Happy Ending: We learn a lot more about the mermaids through Kaori and Mariko's adventures, and while it may also classify as a Bittersweet Ending due to both of them being mermaids, they are together, presumably forever... until one of them is hunted down and killed...
  • Together in Death: Close to it anyway, Mariko invokes the mermaid curse and finds Kaori. Despite Kaori offering up her flesh, Mariko refuses to eat it and willingly waits out the clock to join her friend as a mermaid.

     Yui and Saori 
  • All for Nothing: In the end, no one gains anything. Yui and Reiko beat each other over a mermaid with a false letter. Saori's little lesson to Yui ended up not being worth it for a boy she didn't even want and one of their classmates died due to all three's pettiness.
  • Berserk Button: You try to dress like a mermaid, they'll make sure you have the full experience.
    • Potentially subverted, as the next tale provides a different reason (namely, if the crush happens to be mutual) and if Asami secretly liked the boy, then The Reveal is the real reason they attacked. That a chapter in School Mermaid 2 shows Shinobu dressed as a mermaid with no reaction from the real mermaids adds fuel to this.
  • Body Horror: When the mermaids appear before Asami in the girl's restroom, some of them come in through the faucet and look like grotesque mounds of flesh.
  • Didn't Think This Through: Reiko ropes a girl named Asami into the hunt and has her dress like a mermaid into order to slip in with them and pull a sneak attack. It didn't seem to occur to Reiko after running into Yui and Saori that that would put Asami in danger of being mistaken for a real mermaid and be hunted. Sure enough that indeed is what happens. But the tragedy comes when it turns out Asami's feelings were requited, and the mermaids really don't like that.
  • Downer Ending: Neither Reiko nor Yui get the guy they wanted as Saori changed the letter on the mermaid she killed and had managed to kill a mermaid-fied Asami who appeared in front of her since Asami had the correct letter, allowing Saori to steal the guy whom the two were after. However, Saori now has to live with the knowledge she had unwittingly gotten Asami killed (As she planted the notebook in the locker Reiko and Yui were using, knowing their heated rivalry). She only intended to embarrass Yui and didn't think Asami would be dragged into the hunt. If that wasn't bad enough, the boy she stole the two from reveals he was in love with Asami. Ouch.
  • False Friend: Played both ways here. Yui is the more deliberate example, selfish and mean but acts caring to get what she wants. But the girls of her school consider her very lucky, so Saori hangs around her in the hope her luck will rub off on her, which Yui is all too aware of.
  • Gold Digger: From Saori's thoughts, Yui only wants a certain boy because his parents are doctors and quite wealthy.
  • Heel Realization: As Saori continues to hunt mermaids, she thinks back on Yui's comments to her and starts to wonder why she's even helping such a horrible friend. And has an even more major one after the whole ordeal and the boy's confession to her.
  • Lack of Empathy: Neither Yui nor Reiko show any concern over Asami being taken by the mermaids, only throwing accusations at each other over who was responsible for her fate before Saori gets them to stop fighting and sends them to the mermaid she managed to kill. Heck Yui doesn't even show concern for Saori until after seeing her in school the next day despite not knowing if Saori ate mermaid flesh or not.
  • Loophole Abuse: An odd case in this one, Yui and Reiko eat mermaid flesh but the spell doesn't work for them because it was the wrong letter (due to Saori changing it). Though since they did manage to eat the flesh anyway, it keeps them from becoming mermaids.
  • The Rival: Reiko, the girl who shares a locker with Yui. She gets in on the mermaid hunt after finding the notebook in the locker after Yui forgot it. Naturally Yui isn't pleased by this, especially when she aims for the same "E" mermaid Reiko is after.
  • To Serve Man: We see what happens if the mermaids catch you during their feral phase. They kill you like a pack of piranhas.

     Hidemi and Nanae 
  • Action Girl: Hidemi single-handily knocks out every mermaid that comes after her and even manages to fight off Nanae.
  • Chronic Hero Syndrome: Despite her Tsundere demeanor, Hidemi apparently helps old ladies and refuses to kill a mermaid because they were once human.
  • Deadly Doctor: Nanae, in sense. She's the school nurse of Hidemi's school.
  • Driven by Envy: It's revealed here that the mermaids turn feral if they sense a girl honestly does like a boy and doesn't truly need mermaid flesh (i.e: the feelings are mutual from the boy) to get them to fall in love.
  • Earn Your Happy Ending: Hidemi manages to survive both the mermaids and Nanae's attack, beat the spell's curse and get the guy she wanted in the end.
  • Evil Is Petty: Nanae developed the whole scheme because all of the male students fall for her beauty save for one, the boy Hidemi likes, and wants to use the spell to force him to fall in love with her. What's more she targets the girl who liked him both because she has last name that ended in an "R" (the boy they both like has a last name starting with it) and as a way to get rid of competition.
  • Glasgow Grin: Hidemi inflicts this on Nanae in their struggle when the latter tries to kill her.
  • Good Is Not Soft: Nanae banked on Hidemi being too soft to kill a mermaid and thought for sure she would be an easy target. Unfortunately for her, Hidemi may not be willing to kill but that doesn't mean she can't defend herself.
  • Idiot Hero: Hidemi has shades of this. How do you not recognize your childhood friend's sister?!
  • Invisible to Normals: This story reveals that mermaids will only appear and interact with those who chanted the spell. Otherwise they're unseen by anyone who hasn't.
  • Karma Houdini: Somewhat. Nanae is given a Glasgow Grin for her troubles and quickly limps off afterwards, her beauty she took so much pride in now soiled. But she's still plotting to get an "R" mermaid and slips the notebook into a bookstore knowing some girl will find it and read from the book. Though considering how often the book passed hands to different schools, it's implied she either failed or just gave up (because, really, she can't keep track of every girl that gets their hands on it and even then she's has to actively hunt for said mermaid and we've seen how fast they are). Regardless she's responsible for a number of naive girls of other schools falling victim to the mermaid spell.
  • Loophole Abuse: Hidemi unknowingly stumbles onto one by putting her feeling for the boy she likes on a chalkboard, largely because she thought she was going to turn into a mermaid. However this is considered an Act of True Love in the spell's rules, thus making her exempt from turning into a mermaid as Hidemi has already shown she does love the boy she wants and doesn't need the mermaid flesh. Sure enough, the boy she like visits her in the nurse ward and reveals he likes her too.
  • Losing a Shoe in the Struggle: When Hidemi tries to leave the school after the spell is activated. A barrier knocks her back, knocking off her shoes in the process. She's forced to go around in her socks for the rest of the night.
  • Poor Communication Kills: Narrowly averted, Nanae tempts Hidemi to read the spell when Hidemi thinks back to seeing the boy she like earlier walking home with another girl. Turns out that was his sister.
  • The '80s: This particular story is set in the 1980s.
  • Tsundere: Hidemi reveals her love for Taizou, he reciprocates and yet she still acts standoffish with him
  • Win to Exit: This story reveal that if the spell is activated, it forms a magic barrier around the school that won't let the chanter leave until they either kill and eat a mermaid or the time runs out.

Second Run

Unmarked spoilers in the folder.

     School Mermaid 2 

  • Ambiguously Gay: Shouko was deeply attached to her best friend, Nanae, wanting to spend all their time together and becoming jealous when Nanae got a boyfriend. It's implied that she became the first mermaid out of despair due to believing that Nanae didn't treasure their relationship as much as she did.
  • And the Adventure Continues: Shinobu travels to Shouko's hometown to try to learn more about her and the mermaid curse. Meanwhile, the curse continues with two more girls casting it.
  • Attempted Rape: Because of the effects of the spell on him, Takaaki ignores Saya's pleas to stop, reasoning that she must be willing after going to such lengths to gain his love.
  • Brainwashed: A successful spell cast on a boy works this way, as Takaaki is aware on some level that he loves Saya only because of the mermaid spell.
  • Came Back Wrong: It's possible for a mermaid to come back to the human world if she eats the flesh of her love interest but she'll be Locked into Strangeness for the rest of her life. The way to come back right is to eat the flesh of a mermaid whose letter is immediately after theirs.]
  • Chekhov's Skill: Shinobu discovers early on that she doesn't need to eat the flesh of a mermaid to avoid becoming one, she just needs to drink their blood. This is how she avoids killing the Q Mermaid.
  • Continuity Nod: Since this is a continuation after a long hiatus, it goes through the usual lists of the original series to remind the audience of the rules of the curse: the spell, summoning the mermaids, seeing how fast they are, needing to catch the mermaid with a certain letter if you want the spell to work, the threat of turning into a mermaid if they fail to catch one by dawn and the mermaids turning feral if they sense that a girl's love is requited.
    • Mariko and Kaori from chapter 9 make a cameo appearance in chapter 30, seen among a group of mermaids and still together after all this time.
  • Crazy-Prepared: Shinobu studies the notebook thoroughly and makes sure she and Sakura have the rules down pat before chanting the spell. When they begin the hunt, she makes sure to target any of the mermaids so if they don't catch the intended mermaid, they would at least have a mermaid to feed on so they won't turn into mermaids if the time runs out. That said, she's caught off guard when the mermaids turn feral because the notebook didn't have any information on that. However, Sakura was completely aware of this fact along with the knowledge that it's the mermaids' jealousy that triggers the transformation, and uses this to confirm that Shinobu likes the same boy she does. However, it turns out Sakura is the mermaids' true target and her love is requited, and she gets turned into a mermaid.
  • Darkest Hour: Shinobu and Saya Part 3 for Shinobu. Saya succeeds in stealing Takaaki away from Shinobu, the Q Mermaid appears and tells Shinobu never to come back, and Hidemi also plans to make Shinobu promise not to come back in exchange for everything she knows about mermaids.
  • Destination Defenestration: Shouta's shoved out a window by a mermaid when he reveals to Shinobu what he found out about Kuji Shouko and warns her that no one survives meeting the Q Mermaid twice.
  • Dressing as the Enemy: Shinobu tries this to move among the mermaids undetected. Unfortunately, not only is the Q Mermaid not fooled by it, it alerts her to the fact that Shinobu would be an R Mermaid, which she needs to eat to be brought back to normal.
  • Easy Amnesia: Sakura remembers nothing about being a mermaid or hunting them. Takaaki also doesn't remember being bewitched into loving Saya.
  • Fountain of Youth: It turns out there's a second spell that grants this, but instead of regular mermaid flesh, it has to be the flesh of a mermaid who bathed in the blood of her beloved and regained human form.
  • From Nobody to Nightmare: The mermaid legend started with Nanae's classmate Kuji Shouko, who became the Q mermaid.
  • Gender Bender: When Shuutarou turns into a mermaid, she also gets the feminine body she wanted.
  • Glasgow Grin: Nanae's is finally seen when she eats the flesh of Hayashi after casting the spell for eternal youth. In the present day she reveals she's eaten enough youth-giving mermaid flesh to heal said grin.
  • In Medias Res: Shinobu and Shuutarou Part 1 begins with Shinobu and her classmate Shuutarou just having chanted the spell, and Shinobu (unaware of Shuutarou's gender identity) asking if Shuutarou can really see the mermaids since the spell only works for girls. The story then goes back twelve hours showing what happened earlier in the day.
  • In the Blood: It's strongly implied that the reason Shouko was able to make the mermaid curse real was because she was descended from an actual mermaid.
  • Like Mother, Like Daughter: Just like Hidemi, Shinobu can't bring herself to kill mermaids or eat their flesh, nor does she need to as the boy she loves returns her feelings.
  • Locked into Strangeness: Despite Sakura coming back, she still speaks in a peculiar tone, still has the speed of a mermaid, and generally still acts like a mermaid.
  • Meaningful Name: The Q Mermaid. Short for 'Queen'.
  • Mrs. Exposition:
    • Hidemi's role in "Another Mermaid Legend" is explaining to Shouta and Shinobu what she knows about the mermaid legend, including the previously unknown parts about the second spell.
    • Nanae picks up the baton in "The R Mermaid" when she reveals the origins of the mermaid legend.
  • Nightmare Face: The grin Saya gives Shinobu after stealing Takaaki away.
  • Pseudo-Romantic Friendship: Shouko and Nanae were best friends as students, with the implication of deeper feelings on Shouko's end. Shouko is implied to have become the first mermaid out of despair and jealousy over Nanae seemingly abandoning her for her new boyfriend, and while Nanae does use the mermaid curse to ensnare men and stay youthful and has petty reasons for trying to turn Hidemi and Shinobu into mermaids, her lust for Taizou and her revenge have always come second to reuniting with Shouko.
  • Revenge: It's eventually revealed that Shinobu is the daughter of Hidemi from the end of the first series and Nanae is trying to get her to invoke the mermaid curse as revenge for Hidemi slitting her mouth in the struggle. Yes, Nanae is still trying to enact her petty little plan after all these years.
  • Sequel Hook: At the end, the curse isn't still completely over and Shinobu has traveled to Shouko's hometown to try to learn more about it. The author acknowledges this in the notes that the series got revived before.
  • Supernaturally-Validated Trans Person: Shuutarou is elated at being able to see the mermaids, not just because it means the love spell will work but because it also proves she has a 'woman's heart'.
  • Take a Third Option: The Q Mermaid gives Shinobu two options: kill the Q Mermaid and undo the curse altogether, or let herself become a mermaid so the Q Mermaid can kill her and become human again, also undoing the curse. Shinobu drinks the Q Mermaid's blood instead, which does have the effect of undoing the spells on Sakura and Takaaki, but doesn't eliminate the curse altogether.
  • Wham Episode:
    • Condition to Return: Sakura came back. This was previously thought impossible.
    • Shinobu and Saya Part 3: Shinobu's the daughter of Hidemi Raikou and Taizou from the first series.
    • Morning of Despair: Saya succeeds in stealing Takaaki from Shinobu.
    • The R Mermaid: It turns out Nanae's plan to get an R Mermaid isn't to steal someone, but to try to bring the Q Mermaid—Nanae's high school friend Kuji Shouko and the creator of the mermaid legend—back to normal, as the only way for a mermaid to return to humanity is to eat the flesh of a mermaid whose letter comes after theirs.
  • What Happened to the Mouse?: Despite what Shinobu does at the end of the series, the other mermaids are still missing, including Shuutarou and a girl named Hiromi that Shouta is implied to like.
  • You Are Too Late: Nanae tries one last time to cast the second spell on Sakura. Shinobu had broken the curse by then, so Sakura doesn't turn into a tailed mermaid, and pushes Nanae down the stairs.
  • Your Mind Makes It Real: Somehow, Shouko was able to make the mermaid legend come to life from a play she wrote.