King Desmond makes no bones about the fact that he loathes his son Zephiel and tries to kill him twice. Is it any wonder this wise, gentle boy grows up to be such a bastard in Fuuin no Tsurugi?
Sonia raised Nino as her daughter, but only to use her as a pawn in her evil plans. Then she ordered her assassinated, but thankfully the assassin cared too much about Nino to go through with it.
In Fire Emblem Tellius, Soren's two foster homes treated him like dirt: the woman he stayed with shot constant verbal abuse at him while the sage who raised him afterwards subjected him to intense training (he was only four at the time). Ironically, his own father was less abusive despite being the Big Bad (though he did use the kid as a hostage to lure out his uncle). Given his lack of a stable family it's no wonder he became as snarky and merciless as he is.
Tharja either plays this trope straight or downplays it depending on which supports or conversations you read. In her own supports with Noire, she's mostly aloof towards her outside intensively training her dark magic potential until their A support, where she admits she loves her. She's also very protective of Noire during their talk in the Future Past DLC, and it's said that Tharja mainly took to cursing Noire in her insane grief after her husband's death. However, Noire's supports with her father claim that Tharja was always using her as a guinea pig for her hexes without a second thought and if her father tried to stop it she'd take it out on him. It's usually not suggestible to debate this, however. Tharja's a divisive enough character as it is.
In Fire Emblem Fates, King Garon of Nohr kidnapped the Avatar from their Hoshidan birth parents as a baby and raised them as his own child, but kept them isolated and treated them basically like dirt, even making several attempts on their life during the game. He even implies he'd kill his own blood children at one point! While the real Garon was pretty terrible to the Avatar as well, it's subverted in the case of his own kids. He did care about them and the one who would off them is the slime monster masquerading as him.
Not technically her parents, but the Gestahlian Empire from Final Fantasy VI was the closest that Terra Branford could call her parents due to Gestahl murdering her birthmother and then kidnapping her child, and subjecting her father to various experiments. And, sure enough, their raising her was very much abusive in terms of emotional and possibly other forms of abuse. She was raised in a loveless environment for most of her life, Kefka placed the Slave Crown on Terra to manipulate all of her actions, including burning 50 of their finest soldiers alive, and the one person who was even relatively decent to her, General Leo Cristolph, nonetheless placed the mind control device back on her when they finish training.
Hojo and Lucrecia from Final Fantasy VII did genetic experiments on their son while he was still in the womb in the name of science. The child, Sephiroth, did not take this well. Lucrecia at least harbored some regret for her part in the genetic experiments, even causing her to nearly commit suicide. Hojo, on the other hand, had absolutely no regret for what he did. In fact, he enjoyed every single moment of it even afterwards, and was heavily implied to have manipulated all of Sephiroth's actions and everything in Sephiroth's life/lives.
In Final Fantasy X, Tidus's father often insulted and berated his son for being a crybaby. After believing Jecht had died at sea, Tidus's mother also pined and eventually died. As a result, Tidus harbored bitterness towards his father and never quite forgave him for it. While it's made clear Jecht actually did love his son, the man never, at any point in his life, told him such - throughout both that game and Dissidia, Jecht only admits his love for Tidus when the younger man is either absent or unconscious (or when he himself is dying).
Cid of the Lufaine is revealed in Dissidia to be the father of Chaos, and later the Warrior of light. While he technically only acted according to the circumstances put upon him and his family by the state seeking to exploit his wisdom, he appears to be responsible for the creation of the cycle's of war between Chaos and Cosmos. Thankfully, he later becomes horrified by what his desire for revenge had done and tired to correct his mistakes.
And the cycle continued. In one of the spin-off series, Cyrus is, for all intents and purposes, father figure to an orphan girl whom he raised as a war machine, constantly telling her that everyone is alone in the world. It's implied later that she didn't realize that kindness existed, because he didn't either. Fortunately for her, she got better, and later, so did he.
Cyrus' parents were horrid perfectionists, true, but they were consistent. In Pokémon Black and White Ghetsis goes Up to Eleven in the manner with which he raised N, teaching the boy values that directly opposed what he (Ghetsis, that is) believed in and exploiting N for his own personal gain. The revelation at the end that the boy was merely a tool to those ends is the icing on the cake, the capper to his Garchomp flight across the Moral Event Horizon. You won't find anyone in the know who isn't ready to accept Ghetsis as possibly being the prime exemplar of this trope.
Pokémon Ranger gives us Gordor, who forced his four kids into joining his criminal gang and brainwashing Pokémon. When they finally wise up and leave to embark on their music careers, he just scoffs and goes about his merry evil way. He doesn't give two craps about them and saw them as just more goons.
Kano has this in his Mortal Kombat X ending, where he beats his son's weakness out of him.
In The Elder Scrolls V: Skyrim, Lemkil of Rorikstead blames his twin daughters Sissel and Britte for his wife's Death by Childbirth and abuses them while complaining to everyone in town about them. In fact, if you kill him, you may get a thank-you letter from Sissel.
The Hearthfire DLC adds Lucia, one of the potential orphans the Dovahkiin can adopt. Her parents weren't abusive, but after they died, she was taken in by her aunt and uncle... who decided she wasn't worth the hassle and threw her out. If she's not adopted by the player, she lives on the streets of Whiterun, where only the local beggar is nice to her.
The Tamrielic king of this trope is Lord Harkon, leader of the Volkihar vampires, in the Dawnguard expansion. Centuries before the game, he forced his only child to become a devotee of the daedric prince Molag Bal; it's heavily implied that the ritual to become such involved her being raped by the entity. Later, he learned of a prophecy which could create endless night and thus allow vampires to rule the world. He had no qualms at all with the fact that bringing this about required his daughter's blood. Less horrifically, both he and his wife Valerica tended to use Serana as a pawn in their constant battles against each other; Valerica, at least, eventually apologizes when Serana calls her out on it.
Zettai Hero Project eventually reveals that the Main Character's parents constantly insulted and belittled him ever since he let himself and his sister get kidnapped 8 years ago. However, soon after this is learned it is revealed that the kidnapping was not Main Character's fault (he actually tried to stop it, but his sister was unable to vouch for him due to Trauma-Induced Amnesia). Once this is learned, the parents quickly clean up their act. The trauma of the incident caused the mother and father to constantly argue with each other when they're not busy insulting the Main Character, while his sister lashed out at everyone else because, due to her amnesia, she has no idea why everyone in her family was mad at each other.
Fallout 3 gives us James Hargrave, whose father was eaten by cannibals. Because of this, his mother becomes an abusive drunk and blames him for his father's disappearance. If you kill his mother, he doesn't seem to mind too much.
Cait, your Fighting IrishDark Action Girl companion from Fallout 4, was actually sold into slavery by her own parents. Not as in like "they didn't want to but didn't have a choice", they were just bastards who didn't care about her and wanted the caps. She can't remember a single time they expressed any love or care for her as a daughter and they often verbally and physically abused her. It took Cait five years to get enough money to buy her freedom, and the moment she was free, guess what she did.
Tales of Destiny: HugoGilchrist. Seriously. Twenty years of Tales games and he's still one of the worst parents out there. He's dismissive of Leon, beats him into a week-long coma for getting upset when he thinks Marian killed herself, and there's ambiguous hints he sexually abused Leon in the remake. And in the end, Hugo sends Leon to fight his only friends and floods the mine where they're fighting, knowing his son will most likely not survive.
In Tales of Symphonia, Zelos never had the nicest relationship with his mother, as she was forced into a loveless marriage, even though she "probably loved someone else". When she's killed in an attack that was intended to kill Zelos, her last words to him were "You should never have been born". It's shown in the manga that even before this, she was cold and dismissive of her son, often making the excuse that she's ill or has a headache to get out of having to see him. No wonder he's so messedup...
Lloyd's adoptive father also hits him, but it doesn't seem to be meant to be taken as abuse.
In Dawn of the New World, Emil lives with his uncle and aunt, who regularly abuse him both verbally and physically.
In Guilty Gear X, Sol Badguy takes part in bounty hunting after Dizzy. He finds her and beats her. And it's possible not only that he is her father, but also that he already knew it, when he went after her.
Baek Doosan's backstory in Tekken 2 involves him having to put up with a decidedly unpleasant and abusive father, a result of alcoholism after a crippling injury forced him to leave Tae Kwon Do. How bad did it get? To the point where a sparring session degenerated into a fight in which Baek killed his father by accident.
Becomes a recurring theme in Grand Theft Auto IV, as the main character, Niko Bellic, and his cousin, Roman's, fathers were violent alcoholics who would regularly beat up both their children and their wifes. Dwayne Forge and Packie McReary had similar childhoods, and while the first comments how he felt "nothing" when his father was murdered, the second will at one point open up to Niko and tell that his violent father at one point even attempted and would have succeeded at molesting him, if his older brother, Gerry, had not intervened at the last minute.
In the Japanese version of Earthbound, when Porky and Picky get back home at the beginning of the game, their father chases them offscreen, and can be heard spanking them. In the American version, this is changed to the sound made when enemies in battle use "word attacks," implying that their father was only scolding them.
Then again though; this happens so early in the game people can easily assume it's not supposed to be a "word attack".
In a scene near the end of No More Heroes, it's revealed that Travis' father constantly molested his sister. She eventually gets revenge by killing him, his wife, and attempting to kill his son. Although, having a sexually abusive father is quite possibly the most normal thing about her story...
In Metal Gear Solid 2: Sons of Liberty, Emma was stated to have been sexually assaulted by her second stepfather, for which she injured him in self-defense shortly before graduating from High School. The game itself doesn't specify what kind of assault it was, but the script included in the Document of Metal Gear Solid 2 had in brackets "sexual" right before "assault."
In Metal Gear Solid: Peace Walker, Paz Ortega Andrade, real name Pacifica Ocean, according to her diary tapes, was an orphan, and was apparently adopted by Cipher (in other words, the Patriots faction run by Zero after the split), and she intends to obey Cipher's command, not simply due to her loyalty to the organization, but because she feels as though she has to obey them even if she doesn't agree with their goals because she'll otherwise suffer a fate worse than death if she doesn't.
There's also the fact that they created the clones of Big Boss. The fact that they were created without Big Boss's consent would make this a form of sexual abuse. Oh, and the project that created them also had six of their brothers essentially murdered during development so they could gain strong fetal growth. Then there is the fact that they kidnapped Olga's child, Sunny, after birth, and put her life on the line by having her life being connected to Raiden's vital nanomachines, meaning if he dies, they kill her, and it is heavily implied that even after Raiden defeated Solidus Snake, they still are placing her life on the line as a threat to Raiden, and she grew up completely withdrawn from people until the Patriots finally bit the dust. As a silver lining, Otacon (and to a lesser extent, Snake) do care about her and finally Otacon officially adopts her in Metal Gear Rising: Revengeance
Raiden had it rough too. The only parental figure he ever had was Solidus and he raised him as a soldier and twisted him in every possible way; on top of that, Solidus was the one who killed his birth parents. It takes a LONG time for Raiden to overcome his trauma, thanks to Rose and his son, John.
Bioshock has Sofia Lamb. An incredible list of abuse, mostly of the mental variety-though a degree of neglect etc. Attempting to condition your child in to the 'Peoples Daughter' (an individual who knows everything, or more accurately a conduit for everything), using a serum that reduced a fellow researcher to a sentient tumour, does not a good parent make.
Sofia Lamb may not even be Eleanor's mother, an audio log from her alludes that she did as little to be involved in raising her as possible, possibly even using a surrogate.
Silent Hill. Let's count: Dahlia Gillespie, Leonard Wolf, Thomas Orosco, the unnamed Mrs. Orosco, Walter's parents, Helen Grady, and those are just off the top of my head. There's been, what, one good parent in the series?
At least Harry Mason, the protagonist of the first game, is a Papa Wolf to the max.
Additionally, one of the endings reveals Cheryl's mother Dahlia to be a spouse abuser. It's debatable whether she physically abuses her daughter as well, but the fact that she degrades and beats Harry in front of Cheryl at least stands as emotional abuse.
In Silent Hill: Homecoming, it's taken Up to Eleven with the entire adult population of Shepherd's Hill being abusers of the worst kind. All of them made at least one of their children into a torturous Human Sacrifice, a ritual that has been carried out by every generation since the town's founding, in order to keep the malign occult forces of neighboring Silent Hill at bay. When you arrive during the events of the game, the ritual has failed and the most recent crop of murdered children have come back as monsters to seek revenge. Zigzagged with the protagonist's parents, who did emotionally abuse him, but failed to sacrifice him the way their fellows did with their first-born. And it's implied they only hesitated because his younger brother had accidentally drowned, meaning they'd have no "replacement" child after the protagonist's death.
RELIUS CLOVER. This is the guy who experimented on his daughter, Ada, For Science!, turning her into a weaponized doll, Nirvana. However, he lost interest in the project about halfway through and happily turned to his wife instead, turning her into a much better and accomplished puppet, Ignis, after which he left his family's home and never came back. Meanwhile, his son, Carl, had been forced to finish the experiments he was conducting on Ada, leaving the poor little boy completely traumatized, having to show a lack of compassion and fend for himself as a Vigilante at such a young age. That's an abuse on mental, emotional and financial levles... and he went straight to physical (as in, attempted homicide) when Carl tried to get an explanation.
"You've been a very naughty boy... spare the rod, spoil the child."
We learn very early into Blaze Union that Gulcasa's father beat and neglected him when he was a young child; his father blamed him for his mother's disappearance. We later learn that said mother is also neglectful and emotionally abusive; the last thing she ever did to her child was Mind Rape him into believing himself to be human while sealing his demon blood without his consent. While her reasons for doing so were arguably well-intentioned, it still left Gulcasa with residual brain damage that prevents him from being able to realize that Emilia is his sister when they first meet. And if that isn't enough, she also reveals that she was aware that Gulcasa's father was abusing him, but chose not to come back and do something about it. All of this started from Fantastic Racism, which was also the reason that no one tried to do anything about the abuse. Luckily for Gulcasa, his childhood friends were willing to become parental surrogates, and lovingly helped him grow up mostly undamaged by all this.
Embric of Wulfhammer's Castle . He's the Duchess' uncle, not her father, and the gory details aren't given, but Bad King Greyghast was not above imprisoning, drugging, killing animals, spying on, and sexually abusing his favorite niece to control her.
All of the above happened to Alma Wade, in FEAR thanks to her father, Harlan Wade, and the Armacham Technology Corporation. (Save financial abuse, and that was because she was never old enough to have money in the first place.) Psychic Powers that made her susceptible to emotions, particularly negative ones and especially her fathers', coupled with physical and mental abuse due to being constantly experimented on, ultimately culminated in her being dragged away at her father's orders to be sealed in the Vault in an induced coma. Sexual abuse followed when Harlan Wade and Armacham used her unconscious body as a testing ground for psychic Super Soldiers, impregnating her twice and removing her from her prison only to give birth to the two prototypes. And worse still, she never got to hold her children. Needless to say, when Alma gets loose, hell follows her. So great is his abuse of her that her uber-powerful psychic ghost gets reduced into a scared, crying child whenever she feels The Creep, his psychic remnant, is around. After that, he goes and abuses his grandkids, For Science!. Swell guy.
Where to even start with Fei from Xenogears? After she got possessed by Miang, Fei's mother started experimenting on him, thus creating his Superpowered Evil Side Id, who then was used by his father possesed by the personality of one of Fei's former Incarnations as a Person of Mass Destruction, and that's not even all of it.
Lucien from Runescape was already notorious for being cruel, but the newest Fremminik Saga has confirmed rumors of him having a daughter. Specifically, a half human, half Mahjarrat daughter whom he abuses severely. Every time he speaks to her, he calls her a failure, finally declaring that when he next sees her, he will strangle her. And she just takes it.
Morton's grandfather felt this was the way to instill character in his grandson in The Dream Machine.
In Catherine, both Todd and Archie have issues with women that stem from abusive parents: Todd's dad was a successful businessman, but also a shameless womanizer who constantly belittled Todd, and even attacked him with an axe at one point. Archie, on the other hand, spent most of his childhood locked naked in a basement and was regularly sexually abused by his mother until the day he managed to escape and run away from home.
In The Way, the parents of two characters are revealed to be abusive late in the game. They are Traziun's dad, and Slade's mom.
Borderlands 2 has Handsome Jack, who hooked his Siren daughter Angel up to a machine that pumps her full of Eridium so that he can use her as both a living supercomputer and a catalyst to charge the Vault Key. The sad thing is that despite all of this, Jack does seem to genuinely love Angel in his demented way, but is too insane to see that he's put her in a hellish state of living from which death is the only release. Her death (which she begs for) at the hands of the Vault Hunters drives him into a massive Villainous Breakdown.
Borderlands: The Pre-Sequel! reveals that Nisha, the Sheriff of Lynchwood in 2 grew up with a physically abusive mother who terrorized both her and her father. When her dog eventually went rabid due to a bite from a Frenzyclutch and attacked her, Nisha remembered seeing her mother standing above her and laughing.
Razputin's father in Psychonauts, who puts him through tough, acrobatic circus training rather than allow him the use of his Psychic Powers, actively discouraging the use of the latter. While we don't see any of it, it apparently got so bad that Raz actually started questioning if he was simply trying to get him killed while making it look like an accident. At least, that's what Raz thinks. At the end of the game, we learn that his father is a kind and loving man who just wanted to make sure Raz didn't become over-reliant on his psychic abilities... and he's a powerful psychic himself. Raz simply misunderstood his intentions.
It's hard to say for sure, given the symbolic nature of the level he is in, but there's definitely a possibility that this is the case with Oleander's father, a.k.a The Butcher. Very little is factually known about him, other than the fact that he killed and butchered his son's favorite pet bunny right in front of his eyes, apparently in an attempt to teach him the family business.
Gloria Von Gouten's backstory heavily involves her mother, who abandoned her at a young age in order to pursue an acting career. The boarding house she left her in was not only very harsh, but it forced Gloria to pursue acting herself, which was something she was never even interested in in the first place. Once Gloria finally got out, however, she ended up becoming an even more successful actress than her mother, who soon committed suicide out of jealousy. Its implied that her mother knew full-well that doing this would be emotionally traumatic to her, and it was her death that finally made Gloria go insane.
Clem's father is implied to be emotionally abusive. One of his Campster discussions states "My dad says I'm a total idiot when it comes to canoeing. And most other things. He said he'd rather ride a seal into a pool of sharks than ride in a canoe into the lake with me. Sometimes I wonder if he's right — if I am to stupid for this world."
In Assassin's Creed III (and partially alluded to in Revelations), it's revealed that Desmond's father was physically abusive to him from a young age, ostensibly as part of his Training from Hell, and that this probably played a part (though wasn't the whole reason) in why he ran away from home at 16. In the present day, Desmond hates his dad but is still desperate for his approval. William himself admits that he "did a shitty job" raising Desmond and apologizes for it.
Beyond: Two Souls depicts the protagonist Jodie Holmes' father being verbally abusive to her; he even calls her a monster to her face.
The Binding of Isaac has Isaac, the player character, actually fight the abusive mother, who deprives Isaac of his toys, his clothes, and eventually seeks to kill him.
Queen Larrsa of Mushihime-sama Futari is so protective of Aki that when Aki dies, she goes completely apeshit and wants Reco dead, to the point of sending out entire armies to kill her. Palm, Aki's younger brother, believes that Reco is not a bad person despite having killed Aki. Larsa's response to this belief is to disown Palm. When Palm comes back later, she tries to kill him, using the same amount of strength she would use on Reco.
In Baldur's Gate the strongest contender for the title Most Abusive Parent in the Realms is Bhaal, the Lord of Murder. Bhaal, forseeing his own death, went out and fathered a countless number of children, storing a portion of his divine essence within each of them. Following his death, the priesthood of Bhaal took the children and their mothers to their temples, where he had commanded them to kill the children one by one to ensure his resurrection. To add further abuse to the equation, many if not most of the clergy doing the knifing were the mothers of the children being sacrificed.
[PROTOTYPE]: Alex Mercer's mother was in jail for the first nine years of his life, and when he was returned to her care at age ten, he actually preferred the various foster homes he was shipped around to over being with her.
Ares, as revealed in God of War: Ascension. While not actively abusive, he conceived Orkos with Alecto with the sole intent of creating a perfect warrior to support his Evil Plan to overthrow Olympus, only to disown him when Orkos turned out to be a disappointment. Likewise, the Furies manipulated Orkos into aiding their work in punishing traitors and oathbreakers, only to imprison and presumably torture him when he turned on them to help Kratos.
In Dragon Age: Origins, this is seen in the Dwarf Commoner Warden's origin story. His/her father split years before the events of the game, and the alcoholic mother is verbally and emotionally abusive to the player character and his/her sister Rica.
Flemeth, Morrigan's mother, also fits the trope. Morrigan's dialogue with the player character suggests that she would have liked to be able to love her mother, but Flemeth's various levels of abusive behavior made it impossible. And that's before Morrigan learns that she was conceived as part of Flemeth's ongoing Grand Theft Me method of living indefinitely.
Alistair was raised by Arl Eamon, his biological father's brother-in-law, in Redcliffe Castle. Except he wasn't really raised in the castle; he mostly lived in the kennels with the dogs. He once had to stay in a cage there for an entire day after he accidentally locked himself inside of it. Then, Eamon got married, and the new lady of the house got rid of Alistair within a month - convinced he was her husband's bastard, she made Eamon pack the ten-year-old boy off to the Chantry. He claims that Eamon was good to him, but it's hard to see it that way when you know the details.
In Dragon Age: Inquisition, Dorian's relationship with his father was ruined when he discovered that his father rather than accept Dorian's homosexuality, planned to use Blood Magic to re-wire his brain so he'd be straight. That there was a good chance it would have left Dorian a brain-dead vegetable didn't seem to concern him. Dorian was so hurt by this that it cemented his decision to leave Tevinter to join the Inquisition. His personal quest involves escorting him to meet with his father, who seems genuinely sorry for betraying his son's trust and is there to beg for forgiveness. The Inquisitor can encourage Dorian to forgive him or not; either way, Dorian admits that his relationship with his father will never be fully healed.
And near the end of the game, it's revealed that Flemeth's viewpoint wasn't that she was being cruel to Morrigan, but rather hardening her for how harsh the world can be, and that she was never in any danger of a Grand Theft Me, as it needs to be done willingly. Realizing that her own daughter thought otherwise actually hurts her, which makes sense considering she is one with Mythal, the Elven patron goddess of motherhood among other things.
In To the Moon Johnny's mother turns to be this when it is revealed that she always favored Johnny's twin brother, Joey, over him, and when Joey was accidentally killed by his mother she made Johnny take beta blockers which caused him to forget his childhood and his dead twin brother, and then she forced Johnny into becoming a copy of Joey right down to calling him "Joey", even on his wedding day.
The main characters of Lisa the First and Lisa: The Painful RPG are haunted by their incredibly abusive father. The First takes Lisa through a World of Symbolism showing how she's haunted by Marty's actions, while Brad Armstrong copes via crippling addictions. When Brad meets up with Marty near the end of The Painful RPG, he has become The Atoner, trying to make up for his mistakes by trying to be a better parent to Buddy than Brad ever was.
The Longest Journey: April's adoptive father who's been physically abusing her for years and whom she eventually shoved off the stairs before escaping to Newport.
Played for Laughs in Sonic Lost World. Zomom, one of the Deadly Six, is a fat guy is who obsessed with food. However, a few lines of his dialogue imply that he has low self-esteem, wondering if it's possible to make him look worse than he already does, and telling Sonic not to make fun of his size because it's hurtful. The kicker though, is final quote upon being defeated in the last level.
Zomom: Mom was right, I'm a failure!
Masochisia drives on this. Hamilton and his brother are getting emotionally abused by their mother and physically abused by their father, with both constantly mentioning how they should have killed Hamilton when he was just born, justificating their abusive behaviour with how they lost their first son Albert. While Walter turned out to become so heavily masochistic that their father didn't even want to abuse him anymore and instead locks him into his room, dressed with a muzzle and straight jacket, Hamilton can - depending on how one plays the game - also become heavily masochistic and thus enjoy the treatment and even kill the father.
Implied in Bad Day On The Midway character Ted's backstory. The first things he recalls about his father are his butterfly collection and him hitting Ted.
Many characters in Seraphic Blue have extremely abusive parents who only see them as tools at best and nuisances for being born at worst. Strangely, two of the Big Bad Duumvirate, Leona and Joshua, avert this trope by unconditionally loving their daughter even after she mutates into a Lucifer while some of the other parents turned on their children for far less.
Masaru: Beaten and forced to collect alcohol and tobacco for his father. He was beaten even harder when his father learned he stole these things because he saw it as embarrassing him when Masaru was caught by the police. Also treated like he was a creepy child because he tried to smile his way through his suffering.
Kotoko: Forced into child prostitution by her parents, with her mother going along with her as well, because they felt it would further her career as a child star. Her father, a dental surgeon who was cheating on his wife with his assistant, planned to sell Kotoko into the sex trafficking industry when she hit puberty.
Jatarou: Emotionally abused and neglected, with his father wishing he would die so they could live a free life and his mother forcing him to wear a mask because she hated looking at him. Jatarou came to believe it was because he was terribly ugly, but it was actually because he was so beautiful that his mother felt like she had to put more effort into taking care of him.
Nagisa: Treated as if raising him was a game for his parents. He was forced to study all day for up three or four days in a row to "level up," forced to take medicines and an IV to "restore HP." They also used "Items" (implied to be things like knives) to keep him in line. His father was also a teacher at Hope's Peak who used Nagisa as a test subject to see how much progress a child could make before they reached their breaking point. He didn't seem to be meeting expectations either as it seemed his father wanted to look for a different test subject due to him being less exceptional than desired.
Monaca: Treated very coldly by her family. Her father and brother physically abused her to the point where they ended up confining her to a wheelchair. Although she later reveals that she was just faking this. They were also rather neglectful and emotionally abusive towards her as well. They didn't keep track of what she was doing at all as long as she left them alone and her brother regarded her more like an alien or a parasite living in his house.
In Amongthe Sleep It's implied the main characters Mother is fairly abusive.