Niska is running late from his soundcheck in Brixton, south London. I am expecting the 25-year-old French-Congolese rapper to be slightly the worse for wear: while I wait at his hotel in west London, I see from his Instagram story that he was partying the previous night with his countryman, Manchester United’s Paul Pogba, at a club in central London.

But when he arrives there is no sign of a hangover. Instead, he is polite and charismatic, occasionally peppering his French with English. Niska, who is from Evry, a suburb 25km from Paris, has established himself as a superstar in France with three solo albums under his belt, and he has already started work on a fourth. His last album, Commando, went diamond there, selling more than half a million copies, and he has more than a billion views on YouTube. His infectious take on trap dominated the airwaves in France last summer, and constantly blasted from cars, shisha bars and clubs in the French capital.

Dressed in his own brand of tracksuit, Charo, and Jordans, Niska is assiduously on trend: in the music video for the track WLG, shot on an estate in the suburbs of Paris, he sports metallic jackets, mixes neon lime with black, and wears a tricolour Gucci polo shirt with gold gloves.

“Charo is an abbreviation of charognard [scavenger],” he explains. “It’s a bird that eats dead animals. We took this as a way of describing someone who is determined and keeps going until the end.” But Charo has a double meaning. “In our neighbourhoods, it’s also a way of describing guys who chase girls.” Is he like that? “I was before,” he admits. “I’ve grown up now.” Usually when young men get into music, that’s when they start getting more attention from girls. “That’s true,” he laughs. “Before I did music I would chase them, but now I need to run away!”

Niska’s breakout moment – his “diplomatic passport in music” – was in 2016 when he featured on a track with French music heavyweight Maître Gims. Sapés Comme Jamais, which roughly translates as Dressed as Never Before, was an international success. Niska is reluctant to define the sound he has developed since. “It’s trap, sometimes more dancey, sometimes sad. I sing, but I mix it up with more hardcore rap and trash.” He uses the English word “trash”: what does he mean? “It’s just real,” he says, “it’s the streets and it’s uncensored.”

In the UK, young artists such as chart-topping Streatham rapper Dave have also spoken about these realities: the struggles of making it out of life in deprived areas, and how being successful in music doesn’t necessarily solve people’s problems.

Last December, another London rapper, J Hus, was sentenced to eight months in prison for carrying a knife; the judge recognised his “considerable talent”, but said he had “failed to leave his past behind”. In January, MHD – the biggest name in French rap, was arrested for voluntary manslaughter after his car was allegedly witnessed at the scene of the murder of a 23-year-old man. MHD’s lawyer said he denied involvement and claimed his car had been used by those responsible.

MHD had featured on Versus, a track from Commando. Niska says he can’t speak for MHD’s situation. But as a general point, he has had to take a hard line regarding who he keeps around him. “From the moment you get some success, there’s one thing you need to think about, and that’s the entourage,” he explains. “If you have an entourage that is too aligned with the hood mentality, and doesn’t appreciate what it is that you’re doing, that will be the end.

“That said, there’s a degree of attachment,” he concedes. “This is where we have grown up. It’s the same thing for our parents who come from Africa, who go back every holiday to see those people who they grew up with. We have that attachment, but you need to know how to detach yourself and choose different priorities.”

You can hear this delicate balance – acknowledgement of one’s past while sketching out a possible future – in his music, which blends contemporary western rap with subtle Caribbean and north African references. “It’s all mixed,” he says. “You go to your friend’s birthday party when you’re little, and they’re playing rai [music from Algeria] – whether you like it or not, it becomes part of your culture. After years of hearing it, it feels familiar and does something to you.”

His relationship with the US, still the global leader of rap culture, is more complicated. He kicked off 2019 with Boom Bye Bye, a collaboration with “super cool” US producer Diplo. “I don’t really speak English that well, but he made an effort to talk to me and to try to understand each other,” says Niska. “He’s a big artist, so the fact that he shows that level of respect is definitely appreciated. It was very encouraging.”

But when asked if there are other US artists with whom he would like to collaborate, Niska is hesitant. “I find it hard, because of respect,” he explains. “I don’t think they respect our art, and for a track to go well, there has to be a certain kind of alchemy, something that is reciprocated. If you just send the guy along and it’s just a bit of posing, it’s not worth doing.

“They’re the biggest artists in the world and to be honest they don’t need us,” he says, laughing. “For them, the world is centred around the US, and they don’t know we have this culture with ghettos – it’s like they think there’s nothing there, just the Eiffel Tower, baguettes and pastries. When they come here for fashion week they go straight home, they don’t come to the hood, they don’t see it.”

British artists, he says, have a more integrated approach, citing Skepta, who joined him to work on an as-yet unreleased track. “I liked him. You know why? Because when he came to work on that track, he said: ‘So what are things like where you’re from, can we go see it?’ I liked that approach. [British artists] look for ways to collaborate but the Americans … not at all.”

Niska says he knows how fickle the industry can be. “We don’t know how long this [sucess] is going to last,” he says. “There were many before us who were successful, but today you hear about them and it’s like: ‘He has nothing left, he didn’t manage things well and he’s not successful any more.’”

Behind his cool front, there is anxiety to remain visible. “It’s part of the job, always making new music, things people will like. You ask yourself: am I still relevant? This pressure haunts us, but you manage it. You can’t stress too much or it will impact on your music.”

Despite his youth, Niska seems to have a strong sense of who he is and how to navigate the industry. What are the biggest lessons he has learned so far? “Be wary of your friends. Or be wary of the guys you have grown up with. Look after your family, don’t be too nice, stay humble because that’s important too, work hard, and respect people.” He stops for a moment and nods. “That’s a good start at least.”