After losing both his legs and arms to meningitis when he was just a few months old, the teenager is now one of South Africa's top para-surfers -- and dreams of a chance to showcase his skills at the Paralympics.
"I still feel it's a dream. I've been surfing for two years. I started off as a person who can't even balance," he tells AFP, wearing a red t-shirt and a large smile. "If I could be in the Paralympics, what more could I do? Because that's the only place I'm working myself up to, being in the Paralympics."
Surfing burst onto the Olympic calendar at the last Games in Tokyo in 2021 and will also feature when Paris hosts in 2024.
But the discipline is yet to make its Paralympic debut. Para athletes have high hopes this will happen at the Los Angeles 2028 Games.
Among them are Lessing and fellow 16-year-old Thando Ngcikwe, who on Saturday are to compete in the first stage of the newly launched Global Para Surf League event in Muizenberg, Cape Town.
The pair grew up in Khayelitsha, an impoverished township with a reputation for drugs and crime.
They were introduced to the sport at a "surf therapy" session organized by South African surfing champion and coach Roxy Davis in 2021.
"It was one of the most amazing experiences I've ever had," says Ngcikwe, a double leg amputee.
The two got "addicted" to the sport and soon joined a team run by Davis's foundation.
"Surfing, I feel stress-free. I feel like I'm in my own zone, in my own shell," says Lessing. "I lock all the bad memories and all that stuff behind my head. Just focusing on what I'm doing."
Two assistants help him catch the waves and end his ride. Once on the board, "I surf with my tummy," he says.
In two years, Lessing and Ngcikwe have obtained good results competing at the national level, with the former already making it to the national team.
They are now hoping to make a bigger splash.
"Surfing is in the Olympics [...] Para athletes deserve to be in the Paralympics too," says Davis, the coach.