A woman allegedly subjected her sisters to "systematic sexual abuse" for seven years when they were children, using violence and "emotional manipulation" to keep her siblings silent.
She is accused of holding one of the girls' heads underwater in a bath, and making threats to harm family pets if the pair spoke out.
There was also alleged choking, the use of pressure points to inflict pain, pushing, punching and kicking, the ACT Children's Court heard on Wednesday.
Some nine years after the alleged offending ended, the 27-year-old defendant, who cannot be named, was arrested at her home in Sydney on Monday.
She was subsequently extradited to the ACT to face 72 child sex-related charges, to which she pleaded not guilty at her first court appearance.
Detectives from ACT Policing's sexual assault and child abuse team allege the transgender woman "violently sexually offended" against her younger sisters in Canberra between 2006 and 2013.
All but two of the charges relate to occasions when the defendant was a male child.
Magistrate Jane Campbell did not read the charges aloud on Wednesday, but she noted that the allegations included 24 counts of incest and four of third-degree sexual assault.
There were also 34 counts of committing an act of indecency, four choking charges, and three allegations each of unlawful confinement and using the internet to deprave a child.
Prosecutor Skye Jerome opposed bail on Wednesday, arguing the defendant was likely to intimidate the alleged victims and endanger their safety or welfare if released from custody.
She cited the seriousness of the allegations, saying "violence was regularly inflicted by the accused on the complainants" for sexual gratification and to stop the girls reporting her.
Ms Jerome said the alleged abuse had ended when a complaint was made to the children's parents and the defendant, by then a young adult, "fled the family home".
The prosecutor said the defendant had made admissions to her father when confronted.
She said the woman also recently stopped a detective, who was reading a summary of the allegations to her, in order to say she "expected this to happen some time in her life".
Defence lawyer Kat Duffy applied for the woman's release, noting there had been no contact between her client and the alleged victims for nearly a decade.
Ms Duffy entered the not guilty pleas to all charges on behalf of her client, who told her she left the family home after a "problematic, neglectful and troubled upbringing".
She also said the prosecution case was "not infallible" and there was nothing to suggest the defendant, who worked full-time and took part in volunteer work, would not comply with bail conditions.
Ms Duffy raised concerns about where the defendant, who is undergoing hormone replacement therapy, would be housed in Canberra's jail and whether she would receive the treatment and medications she required if she was remanded in custody.
The defence lawyer said she was worried her client's human rights might be "offended" in the Alexander Maconochie Centre after Ms Jerome told the court she understood the defendant, still a biological male, would be locked up with men if refused bail.
Ms Campbell expressed her "great astonishment" at this proposition as she decided to grant bail, saying being housed with men behind bars would not be in the defendant's interests.
The magistrate was also not concerned about any intimidation of the alleged victims, noting the lack of contact between the pair and the defendant since 2013.
She did say, however, that she believed the prosecution case was strong.
Ms Campbell ultimately imposed bail conditions that included a ban on the defendant contacting the alleged victims and a requirement that she surrender her passport to police and report weekly to a Sydney station.
The case is due back in court on November 14.
