The man accused of murdering schoolgirl Claire Tiltman in Greenhithe admitted going on "midnight walks" armed with knives and an air pistol to find someone to attack.
Colin Ash-Smith, 46, called himself an "animal" and said he was "obsessed" with women, but hated them because he feared their "power".
The former milkman also confessed to stockpiling and carrying knives because they made him feel "powerful" and carrying out savage knife and sex attacks on women.
Ash-Smith is on trial accused of stabbing Claire to death in a dark alleyway on the evening of January 18, 1993, just four days after her 16th birthday.
Jurors at Inner London Crown Court had earlier heard that he has admitted stabbing two young women in 1988 and 1995 and leaving them for dead - but they both survived.
Entering the witness box at Inner London Crown Court for the first time yesterday (November 26), he admitted to trying to murder and sexually assaulting a young mother near a quarry in 1988.
He said: "By that time I regularly went out about once or twice a week in the early hours of the morning.
"I would wait for my mum and dad to go to sleep first and then I would go out. I was 19 or 20.
"That was the first time I started doing it, in 1988. I used to do it quite regularly. I used to call them my midnight walks.
"I was hoping I would see someone and provoke someone into attacking me."
He said he never set out to rape and try to kill a woman. But jurors heard that once he found his victim he subjected her to attack and "humiliation" by taking photos of her in sexual poses.
Asked why he attacked the woman, who cannot be named for legal reasons, he said: "I wanted to feel empowered, that I had control over someone. That I wasn't a doormat."
Ash-Smith obsessively wrote down his "successful" attacks and his other plots in diaries he called his "Assault Plans".
And he gave his attacks percentage marks to score his performance.
He described the attack in 1988 as "95 per cent successful" and his "masterpiece".
Asked why he carried out the attack, he told the court: "I can't remember exactly, but the way I used to be, I would probably say there is no-one to stop me.
"I had a very limited moral compass."
Describing how he feels looking back at that attack, he told jurors: "I always thought I would protect women, would protect people, wouldn't harm people, but I failed miserably, to be honest.
“The one chance I got to show restraint and wouldn't do anything and walk away, and I failed miserably.
"Before that I thought I was a reasonably good person. But, to be honest, I was an animal."
Ash-Smith admitted writing down fake sexual fantasies involving women he knew, and of breaking into their homes to sexually assault them.
Asked by David Nathan QC, defending, if he liked women, Ash-Smith let out a deep sigh.
Then he said: "Yes and no. I didn't like them because I felt they had power over me. My own perception of them was I couldn't trust them because they used me.
"I felt worthless - low self-esteem and I had no confidence around other people. I wasn't happy around most people."
He admitted being "obsessed" with one colleague's wife and breaking into her home armed with a knife, determined to sexually assault her.
He said: "I was obsessed with her. I wanted to sexually assault her."
He broke in through a bathroom window but fled when he heard what he feared was her husband's voice in the living room.
Frustrated, Ash-Smith used a knife to slash her nightgown, which was hanging in the bathroom, before making his escape.
In his Assault Plan journals, he described himself as being in his "full psycho state of mind".
Ash-Smith said he saw the phrase in newspaper reports of his attack and adopted it himself.
And he said he obsessively wrote down his assaults and sexual fantasies "to make it real to me".
He admitted having a stash of 20 to 30 knives, including flick, sheath and butterfly knives, which he carried with him wherever he went.
He also had an air pistol, air rifle, a crossbow and an imitation Magnum in his hoard of weaponry.
Explaining the habit, he said: "I felt safe carrying them. It gave me a sense of security carrying them.
"I found them fascinating. I just liked them. I felt safe, comfortable, powerful with them."
Ash-Smith stood in the witness box with his arms clasped in front of him as he gave evidence.
Two dock officers sat behind him and he was watched by around a dozen of Claire's school friends, who sat in the public gallery.
He denies murder and the trial continues.
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