A 17-year-old boy killed his friend after a fight over using a Bluetooth speaker, a court has heard.
Joshua Taylor died in the early hours of 7 October last year after being stabbed in Sword Drive, Hinckley.
Leicester Crown Court was told the defendant was "fuelled by alcohol" with two knives "seeking revenge".
The defendant, who cannot be named for legal reasons, pleaded not guilty to murdering the 18-year-old, and denied two counts of possessing a knife.
Prosecutor Vanessa Marshall QC told jurors Mr Taylor and the defendant were drinking at Richmond Park with friends on the night of 6 October.
She said the defendant "became angry" and dropped the Bluetooth speaker on the ground, which "infuriated" Mr Taylor.
The pair scuffled and followed one another through a Morrisons car park, the court heard, with Ms Marshall saying Mr Taylor "at some stage that evening had a knife or knives".
In a witness statement one of Mr Taylor's friends saw him with a so-called silver grenade knife earlier in the evening, and a silver small chef's knife in Morrisons.
The prosecutor showed CCTV footage of the defendant entering his home address, and leaving less than two minutes later, allegedly with with two knives, shortly before the attack.
Ms Marshall said the defendant "portrayed himself as a scared young man" in a police interview, and alleged he acted in "reasonable self-defence", but was "clearly behaving as the aggressor".
The trial continues.