Jurors have been given an insight into an alleged killer's behaviour in the hours before he is claimed to have carried out a brutal murder.
Daniel Johnson is on trial accused of killing of David Wilson, 49, who was stabbed to death at his home in Southwick, Sunderland, in the early hours of December 14 2014, which he denies.
The 20-year-old, of Mulberry Gardens, Gateshead, had been at a house party in Sunderland in the hours before the murder, where guests consumed a lot of alcohol, jurors have heard.
One man who had been at the late-night gathering told jurors at Newcastle Crown Court that Johnson had been acting like "a petulant child" at the party.
He told jurors: "He was acting a bit like Jack the Lad, sort of trying to be in control, a bit like the leader of the party sort of thing."
The guest told jurors Johnson had been a "bit of a k**b" that night and added: "Just the way he was acting, like a petulant child, not very friendly to other members there."
He confirmed Johnson had been "showing off" and "doing drinking games" at the gathering.
Another man who had been at the celebration described Johnson "was in everyone's faces" and appeared to be "a bit agitated for some reason".
Prosecutors claim in the hours after Johnson left the party, he mugged Mr Wilson's partner Scott Hoyle in the street and used his key to get into the couple's flat, where he carried out the killing.
Johnson denies murder.
The trial continues.