A Royal Marine commando has been jailed for attacking two women sex workers and another customer because he was unhappy with the service he received.
Nathan Bantick, 22, of Neath, was caught on a massage parlour's CCTV in the early hours of Christmas Day 2013.
Swansea Crown Court heard Bantick felt he had been "ripped off".
He was sentenced to 12 months after admitting assault, actual bodily harm and criminal damage, and faces being discharged from the marines.
The court was told Bantick and his brother Christopher were dressed in Santa hats when they visited Park Lane massage parlour in Swansea at 03:00 GMT after a night out together.
Prosecutor James Hartson said: "Bantick paid for a 30-minute massage and when he was told his 30 minutes were over he became very agitated.
"He started shouting that he hadn't received his full 30 minutes and said he's been mugged off.
"He shouted aggressively and threatened to hit two masseuses if they didn't give his money back.
"He punched the plaster board wall near the head of one of the women, grabbed her and pushed her against a wall.
"He took out his military ID saying: "Who do you think the police are going to want to believe, you or me?""
The court heard how customer Jeremy Rees confronted Bantick telling him: "You can't do that to women."
Mr Hartson added: "Bantick then launched a sustained attack punching and kneeing Mr Rees to the body. He dealt him 20 blows in total."
The court heard Mr Rees suffered permanent nerve damage in the assault and that Bantick also attacked the two women, punching each one of them around three times to the head.
He was given his £40 back before kicking Mr Rees "forcibly to the head".
Bantick admitted assaulting Tammy Davie and Xhenia Thoncheva and causing actual bodily harm to Mr Rees, along with causing £875 damage.
Huw Rees-Davies, defending, said a custodial sentence would result in Bantick's discharge from the Royal Marines.
Judge Keith Thomas told him: "This was a frightening display of aggression.
"You showed your military ID in order to threaten and bully - then you launched a sustained and uncontrollable attack.
"Out of spite and revenge you kicked Mr Rees in the head as he lay defenceless on the floor."