Gary Gallacher was 13 years old when he began his campaign of terror and degradation in 1995.
He threatened his victims with a knife before beating and raping them, the High Court in Edinburgh heard.
Judge Lady Scott warned Gallacher, who is now 34, he would only be released when he no longer posed a threat to the public.
She told him: "You have no remorse. You blame your victims and you do not care about the harm you have inflicted. You take no responsibility. You have apparently no wish to change.
"You have been convicted on 25 charges, involving three victims, which constituted a very serious and sustained course of conduct consisting of physical and sexual violence."
His trial earlier this year heard how Gallacher, who has a history of violence, had first struck in Bishopbriggs, near Glasgow.
He continued to offend for 17 years while living across the city and later in Ayrshire. His crimes did not stop until 2012.
His first victim told how Gallacher had bound her hands with her school tie and raped her, despite her protestations that she was too young to have sex.
During another attack, Gallacher held a knife to her neck and told her she belonged to him.
Gallacher's second victim, who was also a teenager at the time, told his trial how she was slapped, punched, kicked, stamped on and pulled by the hair.
He also brandished a knife at her and repeatedly struck her with it, leaving her with scars.
Gallacher's third victim told his trial how he had assaulted her on her 17th birthday and had also bitten and throttled her.
Lady Scott imposed an order for lifelong restriction on Gallacher and warned him he faced imprisonment for an indefinite period.
The judge ordered he must serve at least five years in jail but told him there was no guarantee he would be released at the end of that period.
Hearing that he posed a high risk of reoffending, she said he would only be freed when he no longer posed a threat to the public.
In sentencing, the judge said she had taken into account that he was a child when his first offences took place and that he suffered from a muscle-wasting disease.
Gallacher was also placed on the sex offenders register indefinitely.
Det Insp Gillian Faulds, who led the investigation, said: "Gary Gallacher is a very dangerous individual who carried out a campaign of violence on three partners who will no doubt be affected by the experience for the rest of their lives.
"Despite the horrific abuse the women suffered, they managed to find the strength to speak to police and testify in court to ensure that he was held to account. I would like to thank the women for their bravery in coming forward."
A violent rapist who first struck as a teenager more than 20 years ago has been jailed for life.