As an overseas geography student at Leeds University, Reynhard Sinaga cut an unremarkable figure.

The 36-year-old from Indonesia was older than most of his course mates but, with his boyish features, slight frame and neatly parted hair, he did not especially stand out.

His black-rimmed spectacles and the fact he had already achieved a degree in sociology gave him, if anything, a somewhat scholarly air.

He had few close friends but those who knew him were aware he was a regular church-goer in Manchester, where he had lived since moving to the UK around 12 years ago.

What they did not know, however, was that this seemingly devout and courteous student was hiding a horrific double life.

Reynhard Sinaga: Most prolific rapist in UK history jailed Show all 11 1 /11 Reynhard Sinaga: Most prolific rapist in UK history jailed Reynhard Sinaga: Most prolific rapist in UK history jailed Reynhard Sinaga was jailed at Manchester Crown Court for life and must serve a minimum of 30 years after he was convicted of offences against 48 men Greater Manchester Police/PA Reynhard Sinaga: Most prolific rapist in UK history jailed The bedroom floor, where dozens of rapes took place, in the the home of Reynhard Sinaga Sinaga, who was convicted on 159 sexual offences including 136 counts of rape in Manchester between January 2015 and May 2017, drugged 48 men and filmed himself sexually violating them while they were unconscious in his city centre apartmen Greater Manchester Police/PA Reynhard Sinaga: Most prolific rapist in UK history jailed A general view of the night club Fifth in Manchester where Reynhard Sinaga watched and picked up men that he later raped Greater Manchester Police/PA Reynhard Sinaga: Most prolific rapist in UK history jailed CCTV grab of Reynhard Sinaga on Princess Street The Indonesian student posed as a good samaritan, offering the men a place to sleep or more drink, the court heard Greater Manchester Police/PA Reynhard Sinaga: Most prolific rapist in UK history jailed Reynhard Sinaga, middle, appearing in the dock at Manchester Crown Court on the day he was charged Julia Quenzler /SWNS.COM Reynhard Sinaga: Most prolific rapist in UK history jailed A general view of the apartment Montana House next to the night club The Factory Greater Manchester Police/PA Reynhard Sinaga: Most prolific rapist in UK history jailed The living room at the home of Reynhard Sinaga His victims – who were mostly heterosexual – had little or no memory of the assaults, which Sinaga filmed on his mobile phone. The men left the flat unaware they had been violated. Greater Manchester Police/PA Reynhard Sinaga: Most prolific rapist in UK history jailed The iPhone 4 taken by a victim and used to convict Reynhard Sinaga Sinaga was caught after one of the men regained consciousness and fought him off, before taking his phone to the police Greater Manchester Police/PA Reynhard Sinaga: Most prolific rapist in UK history jailed Bottles of alcohol which were used to spike victims in the home of Reynhard Sinaga Sinaga is thought to have laced alcoholic drinks with a drug such as GHB, known as liquid ecstasy, to incapacitate his victims Greater Manchester Police/PA Reynhard Sinaga: Most prolific rapist in UK history jailed Greater Manchester Police has urged anyone who believes Sinaga may have approached them on a night out to come forward. Officers say he may have been committing crimes for 10 years Greater Manchester Police/PA Reynhard Sinaga: Most prolific rapist in UK history jailed Mobile phones found in the home of Reynhard Sinaga When Greater Manchester Police examined the attacker’s multiple digital devices, they found 3.29 terabytes of graphic material – the equivalent of 250 DVDs – depicting sexual assaults. Jurors who had to watch some of the mobile phone footage were later offered counselling Greater Manchester Police/PA

By night, Reynhard Sinaga was a serial rapist and sex attacker stalking the streets of Manchester.

Over a period of 10 years, he may have drugged, rendered unconscious and then brutalised more than 190 different men – many of them students aged just 18 and 19, police say.

His depravity was such that it is now thought he is the most prolific rapist ever caught in the UK after being convicted of offences against 48 men.

Now, the full extent of Sinaga’s crimes can be revealed after a judge lifted all reporting restrictions following four trials that saw him convicted of 159 sexual offences against 48 men between January 2015 and June 2017.

Among his victims were straight and gay men, students, professionals and one serving member of the RAF. They ranged in age from just 18 to 35. One was raped eight times in eight unconscious hours. Another was still in sixth form college when he was attacked.

But what all Sinaga’s victims had in common was that he targeted them after seeing they were alone, drunk and vulnerable during nights out in Manchester city centre.

He befriended them, enticed them back to his city centre apartment with the promise of free booze, an after party or, in many cases, the use of a phone charger. Then, police believe, he spiked their drinks with the date rape drug GHB.

“You are a serial rapist who has preyed upon young men who came into the city centre wanting nothing more than a good night out with their friends,” Judge Suzanne Goddard told him at his first trial at Manchester Crown Court. “Having lured them to your flat with the promise of more drink and socialising, you drugged each of your victims, waited for them to become unconscious, undressed them and then raped them in the most callous of ways in your apartment, repeatedly sexually assaulting most of them over a number of hours when they were unconscious.”

Judge Suzanne Goddard told Sinaga: ‘You are a serial rapist who has preyed upon young men who came into the city centre wanting nothing more than a good night out with their friends’ (Facebook/Sinaga)

In each case, Sinaga filmed the sickening attacks on one – and sometimes two – mobile phones.

Jurors were shown the footage in which victims snored as they were raped. Many vomit unconsciously.

So, how did he get away with it for so long?

Quite simply because not one single victim realised or remembered what had been done to them. Some did not even recall meeting Sinaga. Others believed he had helped them by giving them a place to sleep or phone charger during an intoxicated hour of need. One told police his attacker had been “really nice and had looked after” him.

Many victims, indeed, were so embarrassed to have woken up at this small quiet man’s plush apartment, they apologised for being there. They felt they must have imposed themselves. One or two even briefly stayed in touch with Sinaga via text or Facebook – although all ended the interactions after they felt they had become creepy.

What, again, they all had in common was that they blamed their blackouts on over-indulgence on their own part.

Which meant, in the end, it was only sheer chance – and Sinaga’s own arrogance – that led to his downfall.

It was Thursday 1 June 2017 when the 18-year-old who would eventually help catch this serial rapist, who cannot be named, went into Manchester for a night out with friends.

The group were in good spirits, celebrating after taking exams, and they finished the evening in the city’s Factory nightclub.

Little known to them, this was one of Sinaga’s favoured haunts.

The Indonesian lived in an apartment a stone’s throw away in Princess Street. It was a well-heeled place for a student with no discernible means of income – especially one who had the cost of travelling to Leeds for his studies – but then Sinaga, who had first studied here at Manchester University, was from a well-heeled family. His dad is understood to work in finance back home in Indonesia.

From this apartment, the mature student would head out to nearby clubs such as Fifth Avenue, the Ritz or G-A-Y looking for victims. Often, he did not even go inside them. He simply waited on the streets looking for men split from friends.

Sinaga preyed on men leaving clubs who were by themselves (Facebook/Sinaga) (Facebook / Sinaga)

By this point he had grown increasingly bold. He had started to keep souvenirs from his victims including a watch, driving licence and a couple of mobile phones. Over one weekend in April 2015, he had raped two men on consecutive nights. He appeared to want to boast about what he was doing, telling a friend via text that he had turned a straight man gay with the help of a “little potion”.

On this night in June 2017, he saw the 18-year-old, who had become separated from his friends, sat on steps outside Factory at about 12.30am.

The pair engaged in conversation about university and music before Sinaga suggested they go back to his flat so the youngster could use a phone to contact his friends.

The teenager later told police he remembered going into the apartment but nothing after that until he woke up several hours later – with Sinaga naked, on top of him, carrying out a sexual assault.

“As he awoke, which is captured on film,” Iain Simkin, prosecuting, told Manchester Crown Court, “he was lying face down with his jeans and boxer shorts around his knees and, say the prosecution, the naked defendant was in the act of sexually attacking him.

“What followed next was a fight; the defendant repeatedly bit [the victim] and [the victim] struck the defendant several times. Ultimately, he managed to escape from the flat and, once outside, he contacted the police.”

Sinaga was brought from his own apartment on a stretcher and rushed to hospital. The youngster, it later emerged, called police in the first instance because he feared, in his attempts to escape the flat, he may have killed his attacker.

But after the 18-year-old was initially arrested, he was found to have an iPhone in his jeans pocket.

It remains unclear how this got there but it belonged to Sinaga.

And, on it, police discovered the video footage of countless similar sex attacks. A raid on the Indonesian’s apartment later found a second phone and a laptop with more videos.

Sinaga was arrested while still in hospital as police realised they were dealing with a rapist whose crimes were on a scale that was unprecedented.

Officers were set the unenviable task of identifying the more than 190 unwitting victims in the different films. So far, they have traced – and informed – around half of them.

“I am satisfied all were deeply traumatised understandably at the thought of what you had done to them while they were unconscious,” said Judge Goddard.

“None of your victims, when told by the police of the existence of the films, wished to view them or to know the detail of what happened to them,” she added.

Several, it was later revealed in court, had been deeply psychologically harmed as a result of finding out about the attacks. Two men, one aged just 21, had attempted suicide.

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“You have shown not a jot of remorse,” said Judge Goddard. “And, indeed, at times during the case seemed to actually be enjoying the trial process. You clearly have given no thought to the deep distress and lasting psychological damage you will have caused these young men.

Sinaga’s own defence was that the victims had consented to sex. “To some,” he said at one point during the trial, “I may look like a ladyboy, which seems very popular among curious men who are looking for a gay experience.”

He said they were not actually unconscious in the films but merely playing at being dead to fulfil a fantasy. The claims were dismissed as “nonsense” by the judge.