Richard Henry detained for killing Carmel Charles
A trainee painter and decorator has been ordered to be detained in a mental hospital for killing his girlfriend.
Richard Henry stabbed 20-year-old Carmel Charles 17 times in Catford, south London, when he "flipped" on 19 November 2011, the Old Bailey heard.
Henry, 22, who has paranoid schizophrenia, had stopped taking his medication and was a user of skunk cannabis, the court was told.
He admitted manslaughter on the grounds of diminished responsibility.
Michelle Nelson, prosecuting, said: "There was no argument. They were laughing and joking."
But then Henry's uncle heard Miss Charles praying and making noises.
He found her clutching her chest and Henry standing over her with an 8in (20cm) knife.
The jury heard that Henry told police he sometimes thought his girlfriend was the devil and had attacked her after hearing voices saying "kill".
He said: "I just flipped out."
Tests showed he had been smoking skunk for some time but not immediately before he attacked Miss Charles at his flat in Ravensbourne Park.
Judge Richard Hone ordered that Henry be detained indefinitely under the Mental Health Act.
The judge said: "People should know that people who take skunk cannabis and who are psychiatrically fragile can suddenly explode into psychotic and quite awful violence."