Characters: Hekikai No Ai ON
The characters of Hekikai No Ai ON
Seine Miyazaki is a 300 year old girl with an immortal body who Tatsuya invites to live in his home; before that she lived in a cardboard box in a park. In the first chapter, Seine looks like a masochist because she seems to like being bullied. Actually, she becomes close to people who are infected by "mushis", a kind of parasitic, mind-controlling bugs, in order to hunt them. Her hunting ways go against the kind and pacifist Tatsuya's beliefs. Her motive is to avenge her foster father, Simon's death by killing the people of sea, the mermaids. She controls a black snake called Aion that lives inside her. Her weakness is her inability to swim.
- Abusive Parents: Her second father abused and traumatised her to the the point she is unable to swim.
- Action Girl
- Adventures in Comaland
- Animal Motifs: Cats. So much that she portrayed as a Cat Girl in an omake.
- Berserk Button: Shizuki and Yuzuki. Also anything mermaid-related.
- Broken Bird: The first 4 years of her life were horrible, her Parental Substitute was killed in front of her and she's seen lots of people she cared about dying as well.
- Delinquent: She's seen as this by Tsukasa.
- Everyone Calls Him Barkeep: Seine is frequently called "witch" instead of her real name.
- Expy: Of Karin, though only in appearance.
- Girl in a Box: Lived in a cardboard box prior to meeting Tatsuya.
- Haruka Tomatsu: Her Drama CD VA.
- Huge Guy, Tiny Girl: With 19-year-old Tatsuya.
- I Am a Monster
- I Gave My Word: When she finds someone who asks her to stay by his/her side, she stays until they die, tell her to leave, or obstruct her revenge, because she used to be completely alone, too.
- Important Haircut: She used to have a mild example of Rapunzel Hair, but she cut it when she ultimately decided to follow the You Killed My Father path.
- Innocent Fanservice Girl: More like "Indifferent Fanservice Girl".
- I Work Alone
- Le Parkour: With Aion's help. Tatsuya even compares her to a roof-jumping cat.
- Neet: After the Time Skip.
- Not Growing Up Sucks: Seine's had to go through high school many, many times to maintain cover. She even complains about it while talking about her nth school festival.
- Not So Stoic
- Ordinary High-School Student: Subverted.
- Parental Abandonment: She doesn't know anything about her biological parents.
- Power Tattoo
- Pretty Freeloader
- Really 300 Years Old
- Relationship Upgrade/Official Couple: With Tatsuya.
- Sugar and Ice Personality
- Later, she evolved to a Tsundere towards Tatsuya.
- Super Drowning Skills: Seine can't swim. Even in a kid's pool with water-wings, she sinks like a rock. And she fights the people of the sea. The irony.
- Teens Are Short: Her height is 1.46m (4' 7").
- The Nose Knows: She claims infected humans have a different smell than normal humans, and she's learned how to distinguish it over time.
- Tomboyish Sidetails
- When She Smiles: Just look at her. Tatsuya is out of breath.
- You Gotta Have Green Hair
- You Killed My Father: Her Revenge motivation.
- Zettai Ryouiki: Mostly Grade B, sometimes Grade A.
After the death of his parents in a car accident, Tatsuya tries to fulfill his father's last wish of becoming a "high caliber" man. After "saving" Seine from bullying, he insists on trying to help her, even after finding out her real goals. He is kind, optimistic, and believes in other people's good side, which is sometimes an obstacle in Seine's revenge. He is a bad cook, but somehow Seine is not bothered by his food. He has a crush on Seine and wants to be acknowledged as a "high caliber" man by her.Four years later
, he starts going to University at the city.
- Accidental Pervert: Luckily for him, the girls are an Ice Queen and a Fish out of Water.
- Alliterative Name
- Curtains Match the Window
- Because You Were Nice to Me: After Seine encouraged him by saying he can become a "high caliber" man, he fell for her and wanted to be acknowledged by her.
- The Big Damn Kiss: Finally the guy gathers the courage to give one to Seine in chapter 39.
- Bishounen: First the cute kid edition, then later the hot guy edition.
- I Got Bigger: Though 19-years-old Tatsuya looks quite the same as 16-years-old Tat-chan, just bigger.
- Break the Cutie: Let's just say chapter 15 wasn't very nice to him. He gets better at the end of chapter 16 with Seine's help.
- Dogged Nice Guy: To Seine.
- Dragged into Drag: Forced to dress up as a meido as part of his class's cafe staff. And the girls rejoiced.
- Heroic BSOD: At his parents' funeral. Understandable.
- Heroic Willpower/The Power of Love: Why he didn't kill Seine even after being infected.
- In Touch with His Feminine Side: He tries to take care of his house once since his uncle left—make meals, clean, and so on. Minato jokes that he acts like a wife.
- Journey to the Center of the Mind
- Lethal Chef: As Shizuki discovered. Only Seine is not bothered by his cooking.
- Living Emotional Crutch: He became more or less this to Seine after his Journey to the Center of the Mind of Seine and learning why she's so broken. He promised her to always be there for her and, as a bonus, he reminds her of a past friend.
- Kid with the Leash: He's also the only one able to control and stop Seine when she's on a rampage. Also, he could be this to Sheila too.
- Lonely Rich Kid: Until Seine promises him to stay.
- Mamiko Noto: His Drama CD VA.
- Non-Action Guy: Though he's helpful in other ways.
- Oblivious to Love: He can't realize Nagisa has a crush on him since they were around 12 until Minato told it to his face and was horrified that even Seine could read her behavior better than him in only one month.
- One Head Taller -> Huge Guy, Tiny Girl: With Seine.
- Ordinary High-School Student
- Parental Abandonment: His parents died a week before the start of the story.
- Conveniently an Orphan: Admit it, Tatsuya suddenly filling his house with a bunch of young women will be very awkward if his parent were alive.
- Say My Name: "MIYAZAKI-SAN!"
- Secret Keeper: He promises to keep the secret that Sheila is actually a mermaid after doing a Pinky Swear with her.
- Single-Target Sexuality: Seine.
- Teens Are Short: 1.62m (5' 4") at the age of 16.
- Together in Death: With Seine.
- You Are Not Alone: To Seine.
Nagisa is a girl in Tatsuya's class, a long-time acquaintance, and would probably like to get closer to Tatsuya, but ever since Tatsuya found a lost puppy (soon to be Crokette), Nagisa has had violent allergic reactions whenever she is in Tatsuya's house. So she simply stays away from him, even though she loves him.Four years later
she works as a waitress
in a cafe.
- Berserker Tears / Broken Tears: Cried these while choking Seine to death.
- Can Not Spit It Out: She just can't say: "Tatsuya, I love you."
- Control Freak: Mild example. Since she is in charge or her house, she's very strict even with her father.
- Damsel in Distress: When she was infected by Mushis.
- Expy: Of Maki from Karin. They have a similar appearance to each other and are childhood friends to the main character. Nagisa's Belligerent Sexual Tension with Minato also parallels to Maki and Yuuji's Slap-Slap-Kiss relationship.
- Expository Hairstyle Change: After the Time Skip, she's seen with a bob instead of her long side ponytail.
- Fanservice with a Smile: She works as a waitress in a cafe.
- Meido: The cafe's uniform.
- First Name Basis: With Minato. She also used to have this with Tatsuya, but since everybody thought she was taking advantage of him for being rich and her allergies kicked in, she's starting to keep her distance.
- They get back to the first-name basis after the Mushi incident.
- Heroic Self-Deprecation: She thinks she's a bad, selfish person, unworthy of Messianic Archetype Tatsuya. She gets better.
- Like an Old Married Couple / Ship Tease / Belligerent Sexual Tension: With Minato.
- Missing Mom
- More Than Mind Control: When she was infected by Mushis, they used her jealousy of Seine and her fear that Tatsuya knows she wanted his dog dead to break her will.
- Plot Allergy: She's allergic to dog hair. After Tatsuya decided to adopt Croquett, she started to avoid going at his house so he doesn't see her sneezing. All this make her hate the dog that would become Tatsuya's lasting family, droving her into more self-hate and making easier her infection.
- Single Woman Seeks Good Man: She fell for Tatsuya when he defended her from accusations of being a gold digger.
- Unlucky Childhood Friend
- You Gotta Have Purple Hair
Tatsuya's friend and Nagisa's neighbor. More worldly and savvy than his friend, he notices that Seine is not a normal girl.
Tatsuya's little first cousin.
A protege of Tatsuya's father and Tsugawa's family lawyer in charge of Tatsuya's money until he gets old enough. He and Tatsuya have a fraternal relationship, even though they are not blood relatives. He cares and looks after Tatsuya but his job as a lawyer prevents him from being able to be close to him.
Shizuki is the older sister of the "Akuma Twins". Being the older, she is sarcastic, lazy and smart but she has a weak body; she can get sick and tired easily, she cannot swim in pools because of the chlorine, and Tatsuya's food almost killed her (but then, he is
a Lethal Chef
). She has an immortal body and has lived for centuries. She gave immortal bodies to Seine and Simon. Her former name was "Pistis Sophia" but she changed because it was "stupid". She is a Oyaji-con (she is attracted to mature, handsome men).
Yuzuki is Shizuki's younger sister. She is the polar opposite of her sister: she has superhuman strength, is diligent and a good cook, but is a little dumb. She is good-hearted and carries out her Onee-sama's orders. She also has an immortal body and has lived for centuries. She is a Lolicon (she gets excited by children, especially girls) to the point of kissing every child she meets on the mouth (occasionally with tongue
) upon first sight.
She was introduced as a new transfer student, and Tatsuya is given the assignment of teaching her sign language. The youngest of the mermaids, she is despised by all her older sisters except for Ariel. Seine thought she had killed her some 300 years before, but Ariel restored her body almost entirely, leaving her badly scarred about the neck and unable to talk, but with the ability to change herself to have legs and walk about on land. Her true goal is infect a lot of people to order to take revenge on Seine for leaving her without her voice.
She falls in love with Tatsuya.Four years later
she meets Tatsuya as he convinces her to stop thinking of revenge
but she's discovered by two of her sisters and leaves the sea in fear. Tatsuya takes her into his house even though Seine is there; Seine allows her to live, but as a hostage against her sisters
. She seems very jealous of Seine for being the target of Tatsuya's affections.
- Anti-Villain: Type 2
- After 4 years, she evolved to Type 4 since she still hates Seine.
- Anguished Declaration of Love: And with Hand Signals.
- Back from the Dead
- Because You Were Nice to Me: She ordered the infected humans to avoid hurting Tatsuya because he was nice to her.
- Blessed with Suck: She has the ability to turn her tail into legs and move around on land, but can't go far from the ocean. See Heroic RROD below.
- Cry Cute / Inelegant Blubbering: She does one or another.
- Cute Mute
- Fish out of Water: Quite literally, since she starts living in Tatsuya's house.
- Forceful Kiss: The way she infects humans on land.
- At the end of chapter 38, she gives one of these to Tatsuya.
- Girliness Upgrade: After becoming a new Pretty Freeloader, Nagisa put her intro a cute dress.
- Girlish Pigtails: At school.
- Going Commando / Vapor Wear: She doesn't seem know what a bra is or what it's for.
- Heroic RROD: If she stays on land too long, Sheila's body will start to painfully rot, as it's a human corpse from neck down. She can only live safely in the sea.
- Identical Stranger: To Tatsuya's mother, Umi. The reasons for this have not yet been revealed.
- Impossible Hourglass Figure
- Innocent Fanservice Girl
- In-Series Nickname: Shii-chan.
- Morality Pet: To her elder sister.
- Non-Human Sidekick: Anna the sea slug was this for her, aside from being her best friend.
- Pretty Freeloader
- Off with Her Head!: The way Seine killed her 300 years ago.
- Our Mermaids Are Different
- Rapunzel Hair
- Scars Are Forever
- School Uniforms Are the New Black: Sheila is always showed wearing her uniform. Justified; it seems to be her only wardrobe.
- Shrinking Violet
- Single Woman Seeks Good Man: Sheila fell for Tatsuya because he was the only person aside from Ariel to show her kindness.
- Sprouting Ears: Or Sprouting Dog Tail, in her case.
- Talking with Signs: She carries around a notebook wherein she writes what she wants to say. She also learns some Hand Signals from Tatsuya.
- Throw the Dog a Bone: Ariel gave her Enati's lower body after she died so now she's a complete mermaid again.
- And after Seine give up Aion, this returned to her and give her back her voice.
- Tragic Keepsake: She conserved the necklace that Nagisa chose and Tatsuya brought for her even after returning eternally to the sea.
- Unusual Ears: As a mermaid.
Simon was Seine's third foster father and the one person who showed her kindness when she was young. He was known as a magician in his time and was also known to be 1700 years old (about 300 years ago in present time of the story). He bore the "Aion" mark, just like Seine does at the present time, but he had it across the right shoulder, and was able to use Aion's power for his own, unknown, reasons. He died eaten by the mermaids.
They are Seine's prey, in revenge for Simon's death. In-universe, they are the ones who sank Atlantis, Mu, and Port Royal and destroyed Pompeii in order to collect psyche from humans. Up til now, 5 of the 7 mermaids have been introduced. They are Ariel the eldest, Bella the second, Enati the third, Anshu the fourth, and Sheila the seventh
- Affably Evil: Ariel is less of a Jerkass than the rest of her sisters and she and Shizuki only had a Passive-Aggressive Kombat when they saw each other.
- Ambiguously Brown: Ariel.
- Anime Hair: Bella.
- Anti-Villain: Ariel, type 1.
- Artificial Limbs: Enati.
- Asskicking Equals Authority: No matter if you're younger, if you're powerful enough you can take your older sister's place in the ladder. That precisely is Enati's plan
- Attack of the 50-Foot Whatever: Ariel. She's big enough to easily pick up her younger sisters bodily in one hand, and her face alone is taller than Seine.
- Bad with the Bone: Enati uses Simon's skull to make an illusion of him.
- Berserk Button: Hurting or bullying her youngest sister will set Ariel off.
- Big Bads
- Big Sisters Bullies: All but Ariel pick on their youngest sister.
- Big Sister Worship: Anshu to Enati.
- Later to Sheila after she get her lower body.
- Later discovered that the fifth and the sixth have this towards Bella.
- Break Them by Talking: Enati and Anshu to Sheila.
- The Brute: Bella. She's sadistic, ruthless, and loves to cause pain.
- Collector of the Strange: Anshu likes to collect human parts.
- Cute Monster Girls: All of them (even Ariel), except for Bella.
- Cry Cute: Ariel, when she cries, cries from the bottom of her heart and looks so adorable.
- The Dreaded: Bella is feared by all her younger sisters. Ariel, being the eldest and strongest one, is this to Bella.
- The Ditz / The Dark Chick: Anshu.
- Evil Genius: Enati.
- Fangs Are Evil
- Femme Fatalons
- Giant Wall of Watery Doom: Their ultimate weapon.
- Hellish Pupils
- I'm a Humanitarian
- I Have No Sister: Bella to Sheila.
- Just Between You and Me: The fight between Seine and Ariel.
- Lotus-Eater Machine: Ariel put Seine in one of this.
- Master of Illusion: Enati.
- Mind Control: Via Mushis.
- Multicolored Hair: Anshu.
- Off with Her Head!: Enati.
- Our Mermaids Are Different
- Rapunzel Hair: Ariel, Bella and Anshu.
- Short Hair with Tail: The sixth mermaid.
- Sibling Rivalry