Colin Notman, 27, preyed on the 11 year-old at a house in Moredun in 2013 while he played with her and other children.
Notman, then 23, pounced on the schoolgirl for a second time later the same day and pinned her down to the floor by her wrists and raped her again.
He later raped a 13-year-old girl at a house in Baberton in the city in 2015 and sexually assaulted her the following year when he showed up at the same house when she was there, to use the toilet.
Notman, from Gorgie, Edinburgh, pled guilty on Thursday at the High Court in Glasgow to raping both girls - who cannot be identified for legal reasons, and a charge of sexual assault as well as failing to appear at an earlier court appearance.
The court heard Notman visited the house in Moredun between January and July 2013 at a time when the 11-year-old was also there.
Advocate depute Bill McVicar said: “On the occasion referred to in the charge the complainer was playing hide and seek in the house with other children and Notman.
“While they were playing, Notman took the complainer to an attic bedroom and raped her.”
Sick Notman then attacked the girl for a second time the same day, after she finished using the toilet at the house.
Mr McVicar said: “Notman locked the door, placed her on the floor, pinned her to the floor by holding her by her wrists and again raped her.”
Between October and December 2015 while at a house in Baberton, he took the 13-year-old girl to a bedroom and raped her.
Mr McVicar said: “She screamed at Notman and told him that he was hurting her and he stopped.”
The following year in March 2016 he returned to the house when the girl was also there, and asked to use the toilet.
Afterwards, he sexually assaulted her in a bedroom before someone walked in to the room and Notman ran off.
The police were called and Notman was detained at his home, interviewed by officers about the Baberton incidents, and later arrested.
Notman, who appeared from custody, was remanded and will be sentenced by judge Lady Scott on June 14 at the High Court in Edinburgh.
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