He is the gifted child of an African immigrant, from whom he inherited talent and know-how and hugely significant athletic potential.
His father, Roger, came from the Congo, played international football for Zaire, and passed down his genes to his two sons, Romelu and Jordan.
The boys, born in Antwerp, Belgium, wear different shades of blue for their clubs. Jordan, the younger by a year, earns his living in the pale blue of Napoli, down in the south of Italy.
Romelu is, for now, a royal blue Evertonian.
The few times that the brothers play together, they both become "Diables Rouges", Red Devils in the Belgium national team. But where Romelu is 1.91m and 94kg, an immensely powerful attacker, his sibling stands just 1.77m and is usually consigned to the left back role.
Their careers are not entirely commensurate with one another.
Big Rom this weekend is with the Belgium side that, if it could only become the sum of its parts, will go to next year's World Cup among the favourites. Eden Hazard, currently injured, but the undoubted star, along with goalkeeper Thibaut Courtois, help make Chelsea the champions-elect in England.
Kevin De Bruyne is one of Manchester City's most handsomely paid stars.
Dries Mertens (Napoli), Kevin Mirallas (Everton), Yannick Carrasco (Atletico Madrid), Toby Alderweireld and Mousa Dembele (Tottenham Hotspur) and many, many more are the generation of Devils that, surely, offer Belgium a real prospect of challenging the best.
Indeed, those that are fit will travel to Russia's Fisht Olympic Stadium on Tuesday to test the ground for next summer's World Cup.
It is inconceivable that Belgium will fail to qualify for that tournament. Before last night's game against Greece, the Diables Rouges's qualification record was played four, won four, 21 goals scored and one conceded.
The management team for Belgium is the Spaniard Roberto Martinez, assisted by Thierry Henry.
Martinez persuaded Lukaku to sign for Everton while he managed the club, and recruited Henry, one of the best in the business, to pass on knowledge to encourage the strikers available to Belgium.
If Martinez and Henry can get inside the heads of Lukaku and company, they might win the World Cup. If they fail, they will go the way of Marc Wilmots, the former striker who was fired as Belgian coach after Euro 2016.
This is a one-off generation, many of them sons of immigrants, giving Belgium a far greater talent pool than the country ever had.
Maybe coach Martinez exaggerated with a purpose when he described Romelu Lukaku a few days ago as having "the possibility of becoming the best No.9 in world football."
Really? Robert Lewandowski, Luis Suarez and Karim Benzema might just have a say in that.
When the Pole, Lewandowski, is firing for Bayern Munich, he is lethal in front of goal. When Suarez combines with Lionel Messi and Neymar Jr., he is the front runner of the irresistible trident. Then again, Benzema as the pivot between Cristiano Ronaldo and Gareth Bale is Real Madrid's first-choice threesome from a global marketplace.
Lukaku, though, is only 23. He is the leading scorer in the EPL, ahead of Harry Kane, Alexis Sanchez, Diego Costa and Zlatan Ibrahimovic. Their league is a magnet to world stars, not just for fame and for fortune but for the potential to be on a world TV stage that raises their profile beyond even what club football pays.
In recent days, Lukaku unashamedly reiterated that his ambition lies beyond Everton. When the Merseyside club offered him a new five-year deal, making him by far the biggest earner in Everton history, Lukaku made public his desire to move onwards and upwards.
There was outrage and media horror. Lukaku talked of ambition to be the best and to be with clubs beyond the EPL.
He puts himself out here to be castigated. But, he asks, what is wrong with ambition? Why should he not shoot for the world?
Pundits doubt him. They see him as potential unfulfilled.
If Everton has to sell him, and indeed Ross Barkley, the sum they might expect in return might even be £100 million (S$174 million) for the pair.
Chelsea might pay it, rather easily in fact, given that the London club has Roman Abramovich as its benefactor, and anyway Chelsea has been taking tens of millions from China for Oscar and Ramires, and might next summer also sell Diego Costa back to Spain.
Could Lukaku replace Costa?
When the Merseyside club offered him a new five-year deal, making him by far the biggest earner in Everton history, Lukaku made public his desire to move onwards and upwards.
Think back to when Lukaku was barely out of puberty and so precocious that Chelsea signed him up. It smacks of teenage procurement, and that is not exclusive to Chelsea.
The scouts saw Belgium's kindergarten ripening. They signed up Courtois in his teens, and loaned him out to Atletico Madrid. They had De Bruyne, but while Jose Mourinho managed Chelsea, he wanted ready-to-go experienced stars, not moody teenagers.
So Courtois went to Spain, De Bruyne to the Bundesliga, and Lukaku first to West Brom and then to Everton on loan.
Some at Stamford Bridge saw Lukaku as the closest physical specimen to Didier Drogba, but Mourinho still had the Drog, and then replaced him with Costa.
Lukaku eventually signed for Everton, who paid £28 million while Martinez was manager.
Today, there are plenty who doubt that Lukaku is the real deal, or anywhere close to being Drogba Mk ll. On his good days, he does shake off players with bristling force to score wonder goals. On other days, his application fails to convince.
Evertonians, who down the years know a real No.9 when they see one, did a curious thing last week. They heard Lukaku lay bare his ambitions and his doubts that Goodison Park was indeed the place for them.
Yet those fans sang his praises. In part it was because Ronald Koeman, the manager who succeeded Martinez, urged them to do that, reasoning that the best the fans can do is make him wanted.
As ambitious as Everton might be, their priorities include rebuilding a stadium fit for a team to play in Europe. Yes, £100 million will go towards that refurbishment, but maybe Lukaku - and even the local lad Ross Barkley - will be sold in that process of change.
If Chelsea is not the immediate answer, Man U (Mourinho of course), Arsenal or even Liverpool are spoken of as Lukaku's next move. Everton might almost triple its outlay on him, and in football, money generally talks.
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