Tommy Kimpton was constantly teased about his weight, his sticking-out ears, the thick glasses he wore and his lack of success with girls at school.
Kimpton slept with Ben Williams' body on his bedroom floor
What made it worse was the bullies were people he considered friends.
And they included the boy Kimpton admitted he idolised, who he killed by hitting him up to a dozen times with a pool cue, 17-year-old Ben Williams.
During his trial, Kimpton told how he wished he was like Ben, who was slim, funny and attractive to girls.
The teenager told Truro Crown Court: "I did not feel or look the same as everyone else. "I didn't want to be myself. Ben was the sort of person I wanted to be."
But Ben and others mocked him with cruel names, including "dumbo ears", "goofy", "window glasses" and "tank ass".
Kimpton was cleared of murder at the trial - but admitted manslaughter and was sentenced to life in prison.
Bullies repeatedly reminded him about humiliating episodes, including one occasion when he was made to down a shot glass of urine, and a time when photographs of him sitting on the toilet were circulated around school.
His problems started with his troubled family life.
His father, Ross, a taxi driver, was known as the local drunk and died from alcoholism while Kimpton was in jail awaiting trial. His mother, Pauline, also drank heavily.
Kimpton was given alcohol by his grandfather when he was nine or 10 and regularly got drunk from the age of 14 onwards.
Blood from Ben Williams was found up to 3m away
He used money given to him by his father to buy alcohol for his schoolmates at Penryn College, Cornwall, in a desperate attempt to make them like him.
Drugs also became part of Kimpton's life. He started taking amyl nitrate and also spent up to £40 a week on cannabis.
He had been ill after smoking cannabis at his house on the night of Ben Williams' death, something Ben teased him about before he suddenly lost control.
He snatched up one half of a pool cue and using the thick end to beat Ben violently around the head between 10 and 12 times. Spattered blood was found up to 3m (9ft) away.
'Can't bear hurt'
The teenager slept that night in his bedroom with Ben's dead body on the floor before getting up in the morning, showering and changing his clothes.
Kimpton went into Penryn twice on 21 May, to buy a padlock to fix on his door so his mother would not find Ben's body and to buy pills and vodka for a suicide attempt.
In a suicide note left for his mother, Kimpton had written: "Sorry mum, I just can't bear to hurt you any more.
"Believe me, no-one knows how much I hate myself and no-one else can heal my pain."