Lynn Walls met the 14-year-old online, and soon started sending explicit
fantasies to his mobile phone.

The primary school teacher encouraged the lad, who lived in London, to send graphic replies to her messages, and to masturbate during their text sessions.

She also described in disturbing detail what she would like to do to him.

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Millions of players take part in the role-playing adventure, which involves human characters as well as mythical creatures such as orcs, gnomes and elves.

Walls, 42, of Rose Street East, Penshaw, Sunderland, was collared when the boy's father found his mobile phone and contacted the police.

As a result she was suspended from her job at a school in County Durham.

At Newcastle Crown Court today Walls pleaded guilty to inciting a child to engage in sexual activity between November 14 and 26 last year.

Judge Guy Whitburn said: "This is very, very disturbing."

Walls will be sentenced in the week of January 5, and was granted bail in the meantime.

She was ordered to sign the sex offenders' register before she left court.

Judge Whitburn told her: "I warn you, this offence is so serious a
custodial sentence cannot be ruled out."

Defence barrister Andrew Finlay said there was a "substantial background" to the case.