Today, that life of crime is over. Last Sunday, he was merrily trimming senior citizens' locks into smart hairstyles. And he doesn't charge a cent.
Now, the reformed hairdresser is looking forward to being released from the Cape Collinson Correctional Institution and starting a new life.
Every second Saturday of the month, Kit-chai and 10 other inmates get a taste of freedom when they become resident hairdressers at the Chai Wan District Elderly Community Centre.
The visits are organised by the Trim and Growth programme, run by the Society for the Aged and Correctional Services.
Elderly people get haircuts for free, and the volunteers get to practise the skills they learn at the correctional centre.
Last week, Kit-chai, who has been doing this for three months, was thrilled when he was selected to be coached by acclaimed hair maestro Kim Robinson.
"When I found out, I was very happy. Also, the reason I got to participate in the volunteering programme is because I have been showing an improvement," he says.
Australian-born Robinson, who has called Asia home for 30 years, says the collaboration kills two birds with one stone.
"We can help the elderly people - it is important at Chinese New Year to give them a haircut - and assist these kids who have gone off the rails a bit," he says.
Robinson is one of the most expensive hairstylists in town, charging about HK$7,800 for a haircut. He is involved with many charities, and being coached by him is a once-in-a-lifetime occurrence.
Understandably, Kit-chai was nervous. But the friendly, Cantonese-speaking Australian was great at making him feel comfortable. During the group photo session, he reminded Kit-chai to "chok" face - or strike a pose.
And Robinson had some valuable words of advice.
"When cutting hair, it's important that you do it in a disciplined way. It's like an architect with a building. You must have a method," Robinson says.
He adds that sectioning is one of the most important basic skills to master.
Turning serious, the stylist says: "One of the problems we have in our industry worldwide is that the younger generation isn’t taught a proper system.
"So what we're trying to bring back with this group is the old disciplines and structures, something that they can follow. Once they learn these skills, they can use them on anybody."
Kit-chai is keen to learn new techniques.
"When I cut the back, I usually cut it horizontally, from bottom to top. But Kim taught me to cut diagonally, which is a better method, because it's more lively and fresh," he says.
Commissioner of the Correctional Services, Sin Yat-kin, says programmes that connect the young and old have one more benefit: they help inmates see things from their parents and grandparents' viewpoint more easily when they return home.
The time spent with seniors helps them understand and respect the older generation.
Kit-chai's release date depends on his assessment and behaviour. But when he does go home, he now has career ambitions.
He says: "I would like to pursue other hairstyling courses, and broaden my knowledge in the field. Hopefully in the future, I'll get to develop more in the industry."