Day had asked her to send intimate pictures and videos and watch porn, said Gareth Hughes, prosecuting.
When the victim tried to end the relationship with ‘Bella’, Day sent her a message pretending to be Bella’s father saying she had taken an overdose.
When police examined a laptop belonging to the 35-year-old they found three indecent images of children and 25 movies in the most serious level A category, 13 images and 66 movies in category B and 783 indecent images and 27 movies in the least serious level C category.
Day, who is in custody but comes from Ipswich, admitted seven offences of causing or inciting a 12-year-old girl to engage in sexual activity between November 1, 2021, and May 1 last year.
He also admitted two offences of causing a child to watch an image of a person involved in sexual activity and one offence of engaging in sexual communication with a child for the purpose of gaining sexual gratification.
He also admitted being in breach of a sexual harm prevention order (SHPO) imposed at Ipswich Crown Court in December 2019.
In addition to being jailed, Day was made the subject of a sexual harm prevention order for the rest of his life and was ordered to sign the sex offenders’ register indefinitely.
He was also banned from contacting the 12-year-old victim indefinitely.
Sentencing him Judge Emma Peters described Day’s manipulation of the 12-year-old victim as “wicked bordering on evil” and said his grooming behaviour was some of the worst she had ever seen.
She found Day to be dangerous and passed an extended licence period of eight years.
In a statement the mother of the victim described Day’s offences as “sickening” and said her daughter’s innocence had been taken away by him.
The court heard that Day had been given a suspended prison sentence in 2019 for making indecent images of children and later the same year he was jailed for two years later for inciting a child to engage in sexual activity.