An Auckland teenager with a penchant for knives and who stabbed a fellow partygoer to death over a kiss can now be named after he gave up the fight for name suppression.

Theodore Derrick-Hardie was 17 when he stabbed Warren Rosillo at a party in Pakuranga last year.

He had been due to defend a murder charge but pleaded guilty on the first day of his scheduled trial on Monday.

On Friday, in the High Court at Auckland, Derrick-Hardie did not seek to continue his name suppression.

Crown prosecutor Warren Cathart said Derrick-Hardie had been carrying knives in the lead-up to the July killing, the New Zealand Herald reports.

He went to a party where he saw Mr Rosillo, 18, talking to a former girlfriend.

He and his former girlfriend had an argument where he accused her of being unfaithful. She reacted by kissing Mr Rosillo, who responded to the kiss.

Derrick-Hardie grabbed Mr Rosillo by the neck and stabbed him in the chest, face and stomach.

Mr Rosillo died at the scene.

Derrick-Hardie was found the next day at the Heritage Hotel in downtown Auckland and arrested. He will be sentenced on September 28.

Mr Rosillo had moved to New Zealand from the Philippines at age 13. He was nicknamed "WOF" because he was so keen on cars.