Knox's ex-boyfriend described as 'shy, introverted'

For months now, U.S. exchange student Amanda Knox has been the focus of the investigation into the murder of her British roommate, Meredith Kercher.

On Saturday for the first time, the court heard testimony in defense of Knox's former boyfriend, Raffaele Sollecito.

Kercher was found dead in her bedroom in the apartment she shared with Knox on Nov. 2, 2007.

Prosecutors say that Knox, Sollecito and a third man, Rudy Guede, killed Kercher in a sex game gone wrong. Guede has been convicted of sexual assault and murder and sentenced to 30 years in prison.

Seattle murder suspect Amanda Knox is escorted by police officers as she arrives for a hearing in the Meredith Kercher murder trial.

On Saturday, lawyers for Sollecito called longtime acquaintances to testify on Sollecito's behalf.

They described him as a calm young man who rarely used drugs.

"The television described him as a womanizer, in fact he was shy and introverted," said Saverio Pinetti Mofetta, who has known Sollecito for 10 years.

Sollecito's college friend, Angelo Cirillo, said Sollecito was sexually inexperienced but excited about his new relationship with Knox.

Both men were asked about a small knife Sollecito was known to carry. Kercher was found with her throat slashed.

"Raffaele wore his knife as a garment," said De Martino.

Mofetta agreed. "He used it to cut fruit or pizza."

This is a condensed version of a story on the ABC News web site. Read the complete story with photos.