Kou Ichinomiya a.k.a. Recruit
Played by: Hiroshi Kamiya (voice, anime), and Kento Hayashi (drama)The main character. Rec is a straight-laced young man who is good at everything he tries, but also follows his family's mantra, "Never put yourself in debt to anyone" to the letter. Unfortunately, this is what lands him in the strange community of Arakawa's riverbank. He's a teacher in the river village.
- The Ace: He is good at everything, but that also works against his favor in some ways, as it's the result of his father's teachings under the Ichinomiya's mantra.
- Berserk Button: He doesn't like being called "Leech", especially once it started to catch out with the rest of the riverbank's villagers. The first time, he didn't take it well.
- Bishōnen: Takes it Up to Eleven after completing Jacqueline's weight loss program.
- Bookworm: He is by far one of the smartest members of the Arakawa's community. He straightly went to read technical books all the way since he was a baby, as a form of entertainment.
- Brainwashed: In Episode 8 of Season 2, he was charmed by Amazoness's Tengu Brothers to fall for her.
- Butt-Monkey: Since he is the Fish out of Water from the Arakawa's community, he is the only one who doesn't get their idiosyncrasies. He is also often made fun by them, because his normal-world's logic doesn't get along with theirs.
- Debt Detester: His family's mantra and principle is "Never put yourself in debt to anyone". As a result, Rec either avoids any kind of debts, or attempts to pay all of them as quickly as possible.
- Embarrassing Nickname: "Recruit" is not how he would like to be known, especially considering his company's job position (as the heir of the company's president). However, he later embraces the nickname.
- Fish out of Water: Rec is the only member of the Arakawa's village who would be considered as "normal" compared to the rest of the cloudcuckoolanders that live with him.
- I Owe You My Life: Since Rec has always lived under his family's principle, he finds himself in a quandary when Nino saves him from drowning in the Arakawa's river, as she proposes him to become lovers.
- Iconic Item: He always wears a red tie that has the Ichinomiya family's mantra embroidered on it.
- Kansai Regional Accent: Whenever he gets very angry, his speech slips into a Kansai accent for some unknown reason.
- Limited Wardrobe: No matter the ocassion, he always uses a pair of dressing pants, a white shirt, and his red tie.
- Loony Friends Improve Your Personality: Little by little, the more he stays with the rest of the Arakawa's community, the better his own personality changes.
- Masculine Girl, Feminine Boy: To some extent, he is the Feminine Boy to Nino's Masculine Girl. He is said to have the heart of a maiden, while Nino is more The Stoic, because she doesn't know how human girls are supposed to act.
- Neat Freak: Rec is obsessed with cleaning his own living space.
- Non-Idle Rich: The Ichinomiyas are practically rich, and he has a high position in their own company. However, since the Mayor doesn't want any of his own money (and Rec doesn't want to be seen as a "leech"), the best he could do is working as a teacher for the youngest members of the riverbank's community.
- Not So Different: Although he sees Hoshi as a petty person, whenever they team up, Rec becomes as petty as him.
- Official Couple: He and Nino are the main couple of the series. They have been paired since the start as she saves him from being drowned, and proposes him to be in a romantic relationship. It's later revealed that they are literally their respective "other halves", as Nino eventually falls heads over heels in love with Rec, and believes they were meant to be with each other.
- One Head Taller: He is much taller than Nino.
- Only Sane Man: To an extreme, considering the type of place that is the Arakawa's riverbank village, although at some point he just plays along with them.
- "Well Done, Son!" Guy: Rec's relationship with his father is very distant, as they barely see or talk to each other. Rec's motivation for doing what he tells him is because he wants him to recognize his own merits, which he often doesn't.
Played by: Maaya Sakamoto (voice, anime), and Mirei Kiritani (drama)Rec's love interest and the reason he lives under the bridge. A Cloudcuckoolander who believes she's a Venusian (she is actually from Venus, as it is revealed later in the story). She has a strange obsession with fishing some of the creatures that live in the riverbed and provides them as food for the community.
- Ambiguously Human: Nino is presented as someone who could be very human in appearance... unless her unfamiliarity with what a normal human would do (especially a human girl) in a relationship, or the fact that she can breath under water, drop various hints that she isn't actually human.
- Attention Deficit... Ooh, Shiny!: She has a short span of attention when things or situations do not interest her.
- Berserk Button:
- Listening to her most treasured tapes without permission makes her mad enough to climb a telephone pole.
- Trying to take Rec from her, gets some interesting responses that aren't her usual.
- Cloudcuckoolander: Anyone who is an outsider to the Arakawa's riverbed would believe that her Venusian story may be just a fragment of her imagination, but it turns out to be true.
- Expressive Hair: Her hair acts as an antenna whenever she perceives there is something wrong around her. She also used it as a radar for Rec, as a way to know if he was doing well during his emergency trip to Venus.
- Force Feeding: Her idea of hospitality around friends and her boyfriend, which is a Venusian trait, is force feeding them the fishes she catch for dinner.
- Hair of Gold, Heart of Gold: She is a blonde, and her heart is too pure as she is an stranger to normal earthling topics such as "relationships". She can also sense from far away when a person is evil or not.
- Heroic B.S.O.D.: After she finds out that Hoshi used her treasured tapes to record a new song (and all the blame is turned against Rec), she gets very mad and she climbs a telephone pole as a way to isolate herself from the rest of the community.
- Hidden Buxom: Since Nino is always wearing a tracker suit's jersey, no one could notice that she has big breasts.
- Human Aliens: She is originally presented as an ambiguous human who claims to be from Venus, but her claims turn out to be true, as it's revealed that she was left behind by her Venusian parents.
- Innocent Blue Eyes: She has a pure heart and a pure soul, and her naivety is often played with in the rest of the series.
- Innocent Fanservice Girl: She used to take baths normally outdoors, but after a visit from the cops she began to use a Modesty Towel. It's later revealed that, since she is actually a Venusian, she doesn't find it "weird" to be naked, but more "natural", although she feels it as a distant memory of her race.
- Limited Wardrobe: Despite the few dresses that Rec has bought for her, she only wears a school tracker suit (jersey and a pair of shorts) and a pair of shoes. The Mayor provides her lots of them as they are hidden in his underwater bunker.
- Manic Pixie Dream Girl: Nino fills this role for Rec, though her personality doesn't fit very well.
- Masculine Girl, Feminine Boy: She is the Masculine Girl to Rec's Feminine Boy, to some extent, as she is unfamiliar with what a normal girl is supposed to be doing in a relationship. While there are a few women in the community (P-ko and Maria), it's implied she learnt some of her "feminine" manners from Sister and teen idol magazines (as seen in the live action-drama).
- Megaton Punch: Due to her unnatural strength, Nino is quite capable of taking out her anger on someone.
- Mysterious Past: Her past and her "I'm a Venusian" claims are deliberately left out of focus earlier into the series. It's later revealed that she is really an alien, that she was left behind as some part of deal with the Mayor, and that Venusians are always fated to be with their "other halves" (they are always born in a pair of twins, and devote their love to each other, but since her twin died in Earth, she was left behind).
- Official Couple: She and Rec are the main couple of the series. They have been paired since the start as she saves him from being drowned, and proposes him to be in a romantic relationship. It's later revealed that they are literally their respective "other halves", as Nino believes they were meant to be with each other.
- Only Known by Their Nickname: Her real name is never revealed, and she is commonly known as "Nino" or "Nino-san". Her name comes from the tag "Class 2-3" (Ni-no-san) on the tracker suit's jersey that she always wears.
- Parental Abandonment: Her parents left her behind after her twin brother died on Earth.
- Selective Obliviousness: She ignores everything Hoshi is meaning to do for her love, but if Rec does something romantic, she's touched. That is, of course, "if" she notices it.
- She Cleans Up Nicely: Just give her any kind of cute feminine clothing, and she would look gorgeous under Rec (and Hoshi)'s eyes.
- Single-Target Sexuality: Despite her claims that she doesn't want to forget Rec's face or name after she saved his life and proposes him to be lovers (although she didn't know what it really implied), she develops feelings only towards him because Rec was later revealed to be her "other half".
- The Stoic: Her face always shows a melancholic stare, rarely showing a smile. Unless, she shares moments with Rec and the rest of the villagers.
- Sugar and Ice Personality: Nino is notably seen as distant with whatever happens around her, unless she enjoys herself. It's even noted by the Mayor that she has changed once it seems that she fell in love with Rec.
- Victoria's Secret Compartment: Nino keeps a lot of fish inside her jersey's jacket.
Played by: Keiji Fujiwara (voice, anime), and Shun Oguri (drama)The head of the Arakawa community. An odd man that constantly wears a kappa suit, he manages to gather and lead the members of the village with a good amount of (misguided) skill.
- Bunny-Ears Lawyer: Although he is the crazy leader of the community, most of his actions (especially outside the Arakawa's riverbank) are very competent in his own benefit. It's unclear if the villagers are just playing along with him or not at the end of the series.
- Chekhov's Gunman: No one could have guessed at the start of the series that a man who believes that he is a kappa, is actually one of the main moving figures behind the whole plot of the series. He has his own reasons to do so, especially as it concerns the safety of Nino and the secrets that lay under the Arakawa's riverbed.
- Cloudcuckoolander: The Mayor claims that he is a real kappa, but his obvious rubber suit differs. Everyone also buys the idea that he is a mythical creature (even Rec, if only for a few minutes), though, as he tries good enough to act as such.
- Crouching Moron, Hidden Badass: Despite his "mythical creature" claims and his guidance, the Mayor is the most mysterious person who lives on the Arakawa's riverbank. It's heavily implied that he is someone who has enough influence in the outside, as he has saved many of the villagers (such as Rec) when they get involved in dangerous situations that would concern the safety of Nino's real identity.
- The Faceless: It's clearly unknown what his face really looks like, not even when he is doing an illusion-magic performance or when he is out of the kappa suit.
- Full-Body Disguise: Despite his claims that he is a mythical creature, he is only wearing a full-body rubber costume.
- Line-of-Sight Name: The Mayor names people with objects that are close to his sight, once they become members of the community.
- Maybe Ever After: The ending suggests that he is living with P-ko, as he is seen under his real appearance. It's unknown if they are a couple, though.
- Obfuscating Stupidity: The Mayor has had moments of deep insight at times, belying the aloof nature he normally sports. He may be just ignoring some stuff whenever someone points it out to him, but whenever it threatens the riverbank, he always makes it personal.
- Oblivious to Love: Everyone knows that P-ko loves him, but apparently he doesn't know anything about her crush on him. At the end, it's implied that they end up together, or at least, live with each other.
- Papa Wolf: The Mayor is very protective to Nino and her well-being, as she was left behind by her biological parents as part of some deal they had with him.
- People in Rubber Suits: He is not a real kappa, just a man who is always using a rubber suit. Hilarity Ensues when Rec is the only one who recognizes this.
- Team Dad: He is the highest-positioned member of the Arakawa's community, and although he is always Obfuscating Stupidity, he is always going to support everyone in the riverbank whenever they get in trouble.
Played by: Tomokazu Sugita (voice, anime), and Takayuki Yamada (drama)A former famous musician who hit rock bottom and now lives under the bridge. He's always seen wearing his trademark star mask. He's also in love with Nino and always tries to make Rec look stupid in front of her. Under the bridge, he provides all the music for events.
- Butt-Monkey: Once Rec starts living in the riverbank, Hoshi gets on par moments with him. He starts being the butt of the jokes once he finds out that Nino considers Rec as her boyfriend, but not him.
- The Chew Toy: He ends up being put in a lot of painful situations.
- Crazy Jealous Guy: Hoshi gets insanely jealous of Rec, because he also has feelings for Nino. Although she barely notices his own feelings towards her.
- Dogged Nice Guy: Only to Nino. He has known her for a couple of years, and fell in love with her at first sight. His original plan was approaching her little by little to win her heart... until he hears that Rec (who was just a newbie in the community) is "her boyfriend". Instead of feeling fully rejected, Hoshi attempts to be more spectacular to gain her attention (because he notices that Nino and Rec's relationship doesn't advance too much).
- Even Evil Has Standards: He wants and intends to ruin Rec with his own hands. He was initially on board with Rec being hypnotized to "fall in love" with Amazoness... but he helps him break out of it because he prefers to win Nino with his own power, and not playing dirty tricks like this one.
- Expressive Mask: He wears two masks to cover his face. How is it even possible to make expressions on them, is anyone's guess...
- The Faceless: We never see how is Hoshi under his mask, we only know from sketches and short appeareances of his real self, that he often wears sunglasses (due to his former stardom's status, he wants to stay anonymous) and that he has short red hair.
- Fun T-Shirt: Hoshi has some questionable fashion's tastes and he even does his own t-shirts. One very noticeable in the series is the one that says "ORE NO T-SHIRT" ("I'm a T-Shirt").
- Hopeless Suitor: He is persistent to get Nino's attention, even after she mentions that she and Rec are a couple. No matter how many times he tries.
- I Want My Beloved to Be Happy: Once Hoshi sees that Nino and Rec are meant to be together, he realizes that there is no more reason to stay behind with the rest of the Arakawa's community, and he wants to return to his former musical career. He gives a final threat to Rec, with tears on his eyes, that he will never forgive him if he makes her cry.
- Jerkass: He acts as petty and as a Jerk Jock around Rec.
- Karma Houdini: He messed up Nino's treasured tape and Rec gets blamed for it.
- Moment Killer: He voluntarily ruins Rec and Nino's dates because he can't stand them being with each other. However, he even ruins moments involuntarily, when things about those two are getting very serious (such as when Nino and Rec find out that he recorded a song in one of Nino's treasured tapes).
- Not So Different: Hoshi has more in common with Rec than he would expect, especially when it concerns their feelings towards Nino, as they end up acting very childish just to get her attention.
- Only Known by Their Nickname: Due to his anonymity from the spotlight, he is only known as "Hoshi" by everyone in the Arakawa's community.
- The Resenter: He is always going to be resentful towards Rec, and only because he "got the girl".
- Secret Identity: Hoshi used to be a famous singer that even made it to the Oricon charts, but he lost his inspiration (his management never let him use his own songs) and became "Hoshi" to get away from everything.
Played by: Takehito Koyasu (voice, anime), and Yuu Shirota (drama)A former soldier that became a man of the (wrong) cloth once he came to Arakawa. He constantly carries all manner of guns with him and clearly still holds a military mindset. He provides church services under the bridge.
- A Father to His Men: He used to be in the military, and it is implied that he was seen as such in his own squad (and that is also recurrent with the rest of Arakawa's community).
- High-Pressure Blood: When he isn't capable of taking Maria's insults, blood comes out from his face's scar.
- Huge Guy, Tiny Girl: He is the tallest man of the Arakawa's community, so he is seen as a Huge Guy to every woman of the village (with noticeable exception to Amazoness).
- Living Lie Detector: Since Sister was in the military, he can easily react whenever anyone may be lying in front of him.
- Love at First Punch: He met Maria in the middle of a battlefield when she used one of her attacks to leave him bald. He immediately fell head over heels in love of her.
- Mad Bomber: He has an obsession of throwing grenades everywhere, due to his paranoia of being suddenly attacked by an enemy.
- Nun Too Holy: Sister takes seriously his position as a nun, although he is a paranoid soldier who threats the Arakawa's community by the gun.
- One-Man Army: He is a huge man who used to be in the military, and he is well trained in the arts of camouflage and weaponry. The Mayor knows that he is a good person capable of his job, though.
- Only Known by Their Nickname: He is only known as "Sister", and nothing else more.
- Perpetual Frowner: Due to his military's training, he is rarely seen with a smile on his face.
- Person of Mass Destruction: Sister is, perhaps, the most dangerous person in the Arakawa's village, as he is a former soldier who is illegally residing in the Arakawa's riverbank and (probably) Japan.
- Phenotype Stereotype: It's unclear from where exactly is Sister, although Stella's past (as he once directed her orphanage) suggests that he may be English or European as her, too.
- Scars Are Forever: Due to his High-Pressure Blood coming out from a scar that is across his face, it's evident that it frequently opens, and that it will never heal.
- The Stoic: He is a Perpetual Frowner who rarely express emotions... unless his jerkass crush's insults get to him.
- Trigger Happy: Sister is described as a "paranoid former soldier" by some of the villagers, so no one has to wonder why he points them out with guns in some life-or-death situations that may be more of "life" than "death".
- Wholesome Crossdresser: Sister uses a nun's habit (though his military suit is below it), but there are ocassions (either in Imagine Spots or acting scenes) where he will use other feminine clothes such as a schoolgirl outfit, complete with a barette.
Played by: Chiwa Saito (voice, anime), and Eri Tokunaga (drama)A young girl from England who was raised by Sister in an orphanage. She has a noticeable crush on him and appears sweet in general, but she is actually highly skilled in martial arts and is rather accomplished in several underworld trades. She can also transform herself into a musclebound man three times her size thanks to Sister's training. She serves as a yakuza boss for the community.
- Age Lift: In the live-action drama, Stella is portrayed as a teenager (a bit older than the Iron Brothers) instead of a child.
- Clingy Jealous Girl: She doesn't take it well when she finds out about Sister's feelings for Maria. She changes her mind at the end, as she sees Sister and Maria as part of her "family".
- Deliberately Cute Child: She is first introduced as an innocent child (even Rec falls for it)... but she is actually a Cute Bruiser who will beat you up.
- Enfant Terrible: Don't fall for her cuteness... because you will get hurt. And she was trained by Sister, from all people.
- Girlish Pigtails: She uses them as her trademark hairstyle.
- Hair of Gold, Heart of Gold: Subverted. She's young, cheerful and cute, but she's quite the Enfant Terrible.
- Hulking Out: She transforms in a Raoh-kind-of-clone if she gets very pissed off.
- Limited Wardrobe: She always wears a cutesy feminine dress, with some obvious exceptions (as she also uses pajamas when she goes to sleep). Her live-action drama counterpart always wears a mixed variety of clothes, one layer over the other.
- Precocious Crush: She is implied to have a crush on Sister, because he took care of her when she was younger, although it seems that she changes her opinion about those feelings, once the series is ending.
- Undying Loyalty: If she wanted, she could be a yandere towards Sister, but since he raised her for a time period in an orphanage, she is loyal to him in any kind of situation presented.
Played by: Miyuki Sawashiro (voice, anime), and Nana Katase (drama)A former spy who came to live under the bridge. A sadist at heart, she delights in emasculating every man in the community, especially Sister, with whom she has a history. She runs a sheep farm for the community.
- Berserk Button: It's implied that she and Sister were former lovers, since every time Sister slips his tongue into his military's memories, she would attack him with a pair of scissors from across the riverbank.
- Bitch in Sheep's Clothing: Maria is a sadistic farmer that enjoys her free time bullying and insulting the men of the Arakawa's village. She is only sweet to the rest of the female villagers.
- The Bully: As the sadist that she is, she likes to insult the many men around the community (with exception of the Mayor), although her biggest victim is Sister.
- Dark Action Girl: Maria used to be a spy for a country that was on war with Sister's. She knows her fighting techniques and abilities too well, as she can manage a good pair of scissors as a murder weapon similar to a knife.
- Cool Big Sis: She acts as a cool sister, bordering even at Onee-sama territory, although exclusively for the girls and children. The male part of the riverbank's village usually receives a solid portion of bitchiness hidden behind a beautiful smile.
- I Shall Taunt You: Maria's addiction involves in insulting every man of the village, until their spirit to continue living dies along the way.
- Not a Morning Person: She becomes a "monster" if she wakes up earlier than the usual. She is not going to bother to put her "nice act" mask towards anyone (not even women or children) who does so.
- Pet the Dog: Her treatment of Stella after their "duel".
- Rose-Haired Sweetie: The Bitch in Sheep's Clothing variant, as she's only sweet at first glance. She's actually a sadist who loves to bully others. She can be nice to the girls, though.
- Shear Menace: Maria threatens others with her scissors, as if they were knives (due to her military's past).
- The Sociopath: Comedic Sociopathy at most, but in the episode 7 of season 2, she actually goes insane while locked for several days with the people she feels she shouldn't be bullying (ie. girls).
- The Vamp: Maria comes from the "treat men like shit and they'll be fawning over you" variety. It works perfectly with Sister, who fell in love with her back during their battlefield days.
- You Gotta Have Blue Hair: Her hair is pink, which stands out since everyone else in the cast has realistic hair colors.
The Iron Brothers (Tetsuo and Tetsuro)
Played by: As Tetsuo, Yuko Sanpei (voice, anime), and Takuto Sueoka (drama).
As Tetsuro, Ryoko Shintani (voice, anime), and Raito Mashiko (drama)A pair of brothers always seen wearing iron helmets. They claim to have been experimented on and have psychic powers, which are only kept in check by the helmets. They are very lively and run an oil drum bathhouse under the bridge.
- Cain and Abel: Subverted, since Tetsuo and Tetsuro don't hate each other enough to sacrifice one over the other (although it's implied it could happen since they are twins who are growing up, and one of them even has a crush on Stella).
- Deliberately Cute Children: They are a pair of cute children who always do things together. They sometimes mean no harm to others, unless they are obeying Stella's orders.
- Expressive Masks: Since they do not take their masks out, these always express their emotions. This is, however, subverted in the live-action drama, since they look more as tin-luchador masks and they cannot express the meaning of their words.
- The Faceless: Their real faces are never revealed to the readers and the viewers. The few glances of them only happen in the finale.
- Hulking Out: Given the circumstances of training with Sister, they suffer a similar transformation as Stella. Although they only spend transformed as such for a while.
- Mr. Imagination: Rec frequently considers that the Iron Brothers could be "chuunibyou" if any of their claims (being psychics and being pursued by the Government) turn out to be false.
- Power Limiter: Their masks can control their psychic powers, gravity, and they also can shut down the Government's GPS. Or so they claim.
- Psychic Powers: The twins claim that they are psychics, but their powers are never shown in the whole series. Of course, who would tempt them to use them if they are paranoid of the government and if (according to them) their powers are too powerful?
- Puppy Love: One of the twins has a crush on Stella.
- Theme Twin Naming: They are the Tetsujin Brothers, Tetsuo and Tetsuro.
- Wonder Twin Powers: They imply that if they aren't together, their psychic powers may not work. This is the reason of why they fear what would happen if one of them gets caught first.
Toru "Shiro" Shirai
Played by: Hochu Otsuka (voice, anime), and Toru Tezuka (drama)A former salaryman who now lives under the bridge. He can't go anywhere unless he's able to walk on a white line, so he always walks with a field striper.
- Disappeared Dad: Shiro hasn't seen his wife or daughter for six years. However, they still write him letters, and he hasn't divorced his wife. They don't seem to mind that he isn't with them, and they fully encourage his dream of becoming a champion "white-lining walker".
- Nice Guy: He is probably one of the nicest guys you will ever find in the series, as he doesn't act petty as Rec or Hoshi, and he only gets threaten when he isn't fully walking with his line striper, as it's a Serious Business for him.
- Oblivious to Love: He doesn't recognize that Shimazaki loves him with a passion, not even when he gets kidnapped by her after her Rescue Arc.
- Salaryman: He used to be a salaryman, who quit to become the most recognizable "white-lining walker" in the entire world.
- Super OCD: He believes that, if he walks out off his white line, his wife and child would become chicken. And since no one can prove him otherwise, the rest of the community don't want to risk it, either.
- Smarter Than You Look: Despite his greasy-hair and his "caterpillar-sleeping bag" clothes, or the fact that he was a failure as a salaryman, he is actually one of the smartest members of the community. He even gets in charge of a "Change your job" fair inside the Arakawa's community.
Played by: Chiaki Omigawa (voice, anime), and Natsumi Abe (drama)A young woman who lives under the bridge during the growing season. While cute, she's horribly clumsy. She has an unrequited love in the Mayor. She runs a vegetable farm for the community.
- Adorkable: Even when P-ko messes up something, she comes up as a very adorable young woman who tries her best.
- Ambiguously Human: She claims that there is a slight probability that she is actually part vegetable, as her father loves farming, as much as she does.
- Banana Peel: Her "security" system for her farming consists mostly of banana peels that she is sure someone will eventually slip with. However, due to her clumsiness (and shown in her first appearance), she is the only one who falls for it. It's taken Up to Eleven in the live-action drama, too.
- Butt-Monkey: The first one among the girls, starting with her Slippery Skid in her first appearance... or when she gets depressed after the Mayor doesn't recognize her love.
- Curtains Match the Window: Her eyes are red as her hair, probably as one of many hints that she isn't very normal.
- Cute Clumsy Girl: She is very clumsy, compared to the rest of the girls of the Arakawa's community, as she can easily make a misstep.
- Expressive Hair: Her unusual pepper-like hairstyle often reacts to her emotions.
- Fiery Redhead: She not only is a red-haired woman, she also gets too passionate with her vegetable farming (and she claims that she can understand their feelings).
- Hopeless Suitor: She doesn't mind if the Mayor rejects her or ignores that she has feelings for him, she would always pursue his love. It's implied to be averted by the end of the manga, as she is seen living with him.
- Older Than They Look: According to the official info, P-ko is 22 years old, but she looks somewhat younger.
- Only Known by Their Nickname: Everyone calls her "P-ko", and her original name is never mentioned in the series.
Played by: Cho (voice, anime), and Kazuyuki Asano (drama)Rec's assistant from his company. He came searching for Rec when he never came back to the office. He is steadfastly loyal to his boss, but also has a very unhealthy obsession with him. He oversees the running of Rec's company in his absence and helps Kou with his projects under the bridge.
- Arranged Marriage: To Nino, and only because he got (accidentally, thanks to the influence of the Venusian Ghost) "approved" by her parents. He later calls out the wedding ceremony, because he can't betray Rec and his own principles as his assistant.
- Brainwashed and Crazy: He got stuck with Rec during their trip to Venus, although he is shortly eaten by a rabbit-like monster (and this brought several sequels to Rec once he came back to Earth) when they land. He is eventually saved by a Venusian Ghost who brainwashes him afterwards with the only condition of getting Nino back to Venus. He eventually gets better once Rec stops him.
- Everyone Can See It: Everyone knows that his feelings towards Rec could be more than just loyalty... whether they want to ignore them or not.
- Papa Wolf: He is very protective of Rec, ever since he has seen himself as his father's replacement, due to their distant relationship.
- Straight Gay: Takai only acts feminine when he is preparing food or other home made stuff for Rec. Only he knows if he does so because he sees him as his son, or because he wants Rec to see him as a potential lover.
- Subordinate Excuse: Despite his weird attraction to Rec, he sometimes is useful as his assistant.
- You Don't Look Like You: Upon his return after his "supposed" death in Venus, his appearance gets drastically different than his usual self — he looks manly and less Straight Gay and affectionate to Rec.
Played by: Rie Tanaka (voice, anime) and Waka Inoue (drama)Takai's assistant, a beautiful, but somewhat shady lady, who seems to play her own game under both Rec's and his father's heads.
- Beauty Mark: She has a mole under her left eye, that indicates one of her many attractive points as a beautiful woman.
- Brainwashed: She gets known as the "Queen of the Brainwashed" in-series, because she can easily get brainwashed by others.
- The first time is when she goes through a Heroic B.S.O.D., after finding out that Shiro still has a family of his own and that he is still married. To make matters worse, she is contacted by the Mole, a distant acquaintance of The Mayor who wants to reveal the secrets of the Arakawa's riverbed. Not long after that, she becomes The Mole for him.
- The second time is when she gets convinced by a fortune teller who tells her that she needs to change her career. However, she becomes rather useful when Rec and the rest of the Arakawa's community is looking for Nino in the last arc of the manga.
- Enigmatic Minion: Under the Arakawa's community, she becomes The Mole for Rec's dad, since she is more loyal to him than Rec himself. The Mayor then threatens her to finish the research about the riverbank and Nino. She gets later convinced by the same Nino to stay there with the rest of the village.
- The Mole: This is her basic role in the story, as she is hired to infiltrate the Arakawa's village to obtain information about the riverbed and Nino. Once under Rec's father, and another under the Mole's guidance.
- Single Woman Seeks Good Man: She falls in love with Shiro not long after he helps her to get out of Sister and Maria's trap, the first time she tries to infiltrate the riverbank's community. Admittedly, there is a bit of Comically Missing the Point involved, too.
- Stalker With a Crush: Once she gets brokenhearted after finding out about Shiro's family... she becomes obsessed with him so much, that she even kidnaps him.
Played by: Rikiya Koyama (voice, anime), and Takaya Kamikawa (drama)Rec's father and CEO of one of the most powerful companies in the city, if not Japan. He firmly believes in never being indebted to anyone and has instilled that in his own son, for his entire life. A cutthroat businessman, he gets what he wants whenever he wants it and proudly stands tall over his accomplishments.
- Disappeared Dad: He had a rare presence in Rec's childhood (he would rarely eat with him in the table and such), while the "dad" role went to Takai, one of his assistants. It's suggested that he feels resenful over his wife's death, so he maintains a distance from his son.
- Four Eyes, Zero Soul: Subverted. He's very harsh and curt with Rec, but he does have some love for his son, as he doesn't want to harm him.
- Humiliation Conga: In a situation that briefly parallels to his own son's first encounter in the Arakawa's bridge (his pants get robbed, Nino talks to him while he is in his underwear), he leaves the place all classy and looking so cool he annoys the policeman.
- Papa Wolf: Despite his intentions towards Rec's life, he protects his son from the sidelines.
- Scary Shiny Glasses: Due to his strict personality and rare presence in Rec's life, there are times that Rec gets uncounsciously scared by his glasses-wearing image...
Played by: Yuuichi Nakamura (voice, anime), and Taro Suruga (drama).Once a master hairdresser and an attractive man, he got sick and tired of his lifestyle and ran away with little more than a katana from his family's house. After an accidental meeting with the Mayor under the bridge, his "samurai spirit" was awakened, and now he speaks in an older Japanese dialect and wears a topknot as he lives with the community by the Arakawa river. He still uses that same katana to cut the hair of the Arakawa people.
- Everything's Better with Samurai: He is considered as the "last" one of them, as lampshaded in his nickname. He is also a fan of Ryouma Sakamoto, and he also writes a blog under this identity.
- Hopeless Suitor: He has a crush on P-ko, and he later learns that she is never going to stop loving the Mayor, despite her attempts. He sometimes self-deprecates himself knowing that she would never change her opinion on him.
- Important Haircut: He used to be a normal hairdresser, until he got sick of his lifestyle and ran away from home. He cut off his hair as a "new beginning" once his "samurai spirit" was awakened in the Arakawa's riverbank.
- Keigo: His formal speech towards the rest of the villagers, reflects his old-fashioned sense as a "samurai".
Played by: Fumihiko Tachiki (voice, anime), and Norihisa Hiranuma (drama)Rumored to have once been the boss of a Yakuza-like gang of bird-headed people, and supposedly betrayed their trust when he fell in love and eloped with the bee princess Jacqueline. It's debatable how much of that story is true, but what is known is that he is deeply in love with her.
- Always Save the Girl: As long as the girl is Jacqueline, he is always going to be there for her.
- Even the Guys Want Him: Or, at least, they cannot help swooning over his manliness (in Rec and Hoshi's cases).
- A Father to His Men: How the birds' yakuza sees him (he is their "big brother"), since he is always in the peak of sacrificing himself for their sake... and the sake of the riverbank's villagers.
- Interspecies Romance: Due to their eccentric natures, both him and Jacqueline consider their relatioship as somewhat forbidden, since they are a cockatoo and a bee, respectively.
- Satellite Character: He almost always appears alongside his partner, Jacqueline.
- Sickeningly Sweethearts: He is tsundere towards Jacqueline, although he is madly in love with her. That was the reason alone he had to betray his mob group.
- Single-Target Sexuality: He has no eyes for other woman (or man), except for Jacqueline.
- Tsundere: He is a tsuntsun towards Jacqueline, as he may look aloof from her. But his dere side shows off when he really means she is the world to him.
- Yakuza: He was part of a mob group, and understands how the underworld works — he has seen his comrades suffer through several incidents and he even sacrificed himself over his love to Jacqueline, who was also a mob queen (depending on the source, she was either the lover or wife of Billy's own mob boss, or she was the lover of a rival mob's boss).
Played by: Yuko Goto (voice, anime), and Kurume Arisaka (drama)A woman in a bee costume who fell madly in love with Billy and is practically inseparable from him. She runs a day spa called "Queen Bee" under the bridge.
- Beware the Nice Ones: Despite her fragile appearance and politeness, she is still a former yakuza queen who quit her old life to be with Billy. If someone pushes her buttons enough, she wouldn't mind to use her former yakuza's kimono as a way to show her power's influence to anyone who threatens her pacific life.
- Damsel in Distress: She seems to be physically helpless, which allows Billy to always come to the rescue.
- Dragon Lady: Prior to coming to Arakawa, she was a yakuza queen who had a great power in her mob.
- Interspecies Romance: This is how she interprets her relationship with Billy, since she is a "queen bee" and he is a bird.
- Satellite Character: In almost every single one of her appearances, she appears next to Billy, her lover, because they are an inseparable couple.
- Sickeningly Sweethearts: She is madly in love with Billy, to the point that they always act very endearingly to each other, despite Billy's tsundere nature.
- Single-Target Sexuality: Jacqueline doesn't have any eyes for any other man than her Billy.
Captain a.k.a. "Potachi"
Played by: Tomokazu Seki (voice, anime)A mangaka who publishes his works under the pen name "Potato-chip Kuwabara." A total sci-fi geek who likes to think of himself as a space captain defending the Earth from aliens. He becomes interested in the people living under the bridge when he sees Nino, who he thinks is a Venusian plotting to destroy the planet.
- Brainwashed: He gets involved in some conspiracy's organization that promises him to reveal some of Nino and the Arakawa's riverbed's secrets.
- Captain Space, Defender of Earth!: He believes that his real role in the world is that he should protect the world from evil venusians, and his way to warn people about it, is through his sci-fi manga's pages, which are inspired from "real-life events".
- Creator Breakdown: In-Universe. He ran away from his career as a mangaka when his editor kept forcing him to draw Moe manga instead of sci-fi.
- The Mole: His own desire to defend the Earth is what the Mole's organization wants to use in their own benefit, although he still has some affection to the Arakawa's community. He knows that the organization is full of "bad" people, but his only motivation to keep doing so is because he just wanted to be a hero, no matter what side he takes.
Played by: Yuu Kobayashi (voice, anime)A mysterious Amazon woman who lives down the river, outside the riverbank's community. Her personality constantly shifts from that of an intimidating warrior to a high school girl. She's rarely seen without her cell phone and has a love of all things made in Saitama. She works for an unknown person and is often accompanied by a trio of "tengu" (guys with tengu masks and bikini tops worn over their t-shirts) who act like her "big brothers".
- Amazonian Beauty: She has the body of an Amazon, but the heart of a high school girl.
- Hopeless Suitor: She thinks that Hoshi is never going to pay attention to her at first, as he still holds his feelings for Nino.
- No Guy Wants an Amazon: She believes that no man would love her, because she is too forceful onto the guys she likes. Her "brothers" seem to think otherwise, though, as they often encourage her to become more "girly".
- She Cleans Up Nicely: Without the heavy make up, and despite the Amazonian-body and disguise, she can look really pretty and very normal, just like a high school girl. However, she gets easily too embarrassed by it.
- Stripperiffic: Her outfit goes along with the Amazon warrior theme of her disguise, and it leaves very little to the imagination.
- Tiny Guy, Huge Girl: To both Rec and Hoshi, as she is taller (and stronger) than both of them.
- Tsundere: Lampshaded by Rec and it's as creepy as it sounds, because she can be a very violent tsuntsun.
- Uncanny Valley Makeup: Her make-up makes her look as she could be straight from a "horror" movie.
- Valley Girl: Her Saitama dialect is translated in the anime and the manga as a "valley girl" accent. Her fixation in many accesories that would make her look girly adds the full "girl of the valley" image.
- Younger Than They Look: Amazoness is still a teenager (who is likely to be 16 years old), although she is very tall and buff.
The Tengu Brothers
Played by: Yuuichi Nakamura (voices, anime)The trio of "tengu" that live with Amazoness in the south part of the Arakawa's riverbank. They consider themselves as her "older brothers", as they often worry about her, especially in love matters. They will do everything for her, even if it implies using their mystical powers to obtain results. Amazoness refers to them as "women", since they use bikini tops over their t-shirts.
- Big Brother Instinct: They feel like they are responsible for the well-being of Amazoness, and they often take it overboard, even hypnotizing the parties involved to "convince" them that they "love" her.
- The Faceless: They hide their faces under tengu masks, and there are rare sights of their faces in some manga panels, when they talk serious about their "sister".
KameariA very famous idol and model in Japan.
- Ascended Extra: From a passerby mention and Running Gag earlier, Kameari plays a major role towards the ending of the series. He even makes a personal proposal to Rec to join the riverbank's community after he finds out that he is as weird as the rest of the Arakawa's community.
- Even the Guys Want Him: Rec, Hoshi, and Last Samurai swoon over him a LOT. They tend to "invoke" their Kameari-tis when they have to think as "teenage girls". He gets particularly scared of this when he finally meets Hoshi and Last Samurai in the riverbank.
- Maybe Ever After: At the end of the manga, it's implied that he and the Venusian Ghost got together, as they left Earth.
- Walking Spoiler: Since his appearance and role is extended in the manga, long after where the anime was left, no one would have guessed that he would have played a bigger and major role in the last arc of the series, instead of just being a passerby mention from any of the Arakawa's villagers.
- Willing Channeler: Kameari accepts being the human host of the Venusian Ghost as part of a deal regarding his nudity's obsession. It's this possession where the Venusian Ghost realizes he has a mutual connection with him as his possible other half.