An estimated one million people were killed during a 100-day period, among them Tharcisse's father and two brothers. Aged 13, he was forced to flee his home and then the supposed safe shelter of a camp to stay alive with his mother, sisters and remaining brothers.
However, he has been able to slowly and steadily heal his emotional wounds thanks to an unlikely source of solace -- the game of rugby.
"I feel like I'm running to the future," he adds.
"It can bring you great joy and you don't think about the past. When rugby started here, people were still thinking about the past, about the genocide. The game just brings so much unity with other people."
'Seeking a purpose'
Prior to 2001, rugby barely existed in the "Land of a Thousand Hills."
Bar the occasional game between ex-pats, it was unheard of in the East African country. Football was king, and still is -- the other key sports in Rwanda being basketball, volleyball and cycling.
But that all changed in 2001, with the visit of a British charity worker seeking to find a purpose in life.
Emma Rees was unsure what to do after completing her university degree, and traveled to Rwanda with Voluntary Service Overseas
She started throwing around a rugby ball with school kids, and has since become a sort of modern-day William Webb Ellis -- the schoolboy credited as being rugby's original founder in the 1820s -- for one particular country.
Rees first took the game to schools, and the following year the Ministry of Sport granted approval for the formation of the Rwandan Rugby Federation. Two years later the Friends of Rwandan Rugby
charity was formed.
'Trying to move on'
The charity's treasurer Deena Aiken, a former Australian rugby international, spent 14 months in Rwanda at one point in the role -- as she puts it -- "living in a mud hut."
"Without doubt, the reason I still volunteer 15 to 20 hours a week is because of the stories you hear," she says, citing one tale from a rugby development officer in the north.
"There were two families there that lived next door to each other but had not spoken since the early '90s," Aiken says. "But the children started playing rugby and suddenly the families were coming back from rugby and talking. They finally had something to talk about.
"And there's countless stories like that. You hear stories of how boys would dress up like girls in a dress, or hide in a swamp for a whole month just to escape, and these are guys I know today. They don't talk about it very often because they're all trying to move on."
Modern-day Rwanda is irrevocably interlinked with the genocide, nearly quarter of a century later.
The volume of Tharcisse's voice drops as he discusses it. "Two brothers and my father died," he says. "But for me now, today, I feel okay. I feel interested in life and I think my family are proud.
"I remember when I first invited them to watch, they thought, 'What is this odd game?' But they're very happy that rugby has given me a job. It's changed my life."
'Dreams come true'
Rugby is still very much in its infancy in Rwanda, and did not receive full international membership until August 2015.
The Silverbacks are ranked 96th out of 103 nations in the World Rugby listings, sandwiched between the Solomon Islands and Bulgaria. The team played in the fourth tier of the 2016 African Cup, losing to DR Congo in the East Division final in Kigali.
Tharcisse was one of Rees' first converts, playing at his secondary school, Groupe Scolaire Shyogwe. Initially he was bemused, but became enraptured with the sport.
It has become his job as the boss of Rwandan Rugby -- based in the capital Kigali -- to spread the message of the game, particularly in schools.
He now has five development officers under his tutelage, and the sport is played in 74 primary and 56 secondary schools.
With his own international career over -- Rwanda currently play the likes of Zambia and Mauritius -- Tharcisse allows himself to dream about the future.
"It's happened already so I can say that dreams come true," he adds. "Maybe we can get to the stage where we're competing for the World Cup in a few years time. We're also pushing in sevens and trying to play against sides in Kenya and Uganda that are are in the World Series. These are countries we need to learn from."
There are nine teams in the Rwandan League and some 600 senior players, while the sport has the backing of the country's premier Paul Kagame. In addition, Rwanda has competed at the Kowloon 10s, an event associated with the Hong Kong Sevens.
Aiken helped teach Kagame's children how to play rugby, while former Scotland national XVs coach Frank Hadden and sevens specialist Scott Wight have visited to provide coaching support, and Welsh clubs have donated kit for players to wear.
The Scottish link started at the 2014 Commonwealth Games in Glasgow, when the country's local councils were asked to "Support a Second Team."
Rwanda was paired with East Lothian, and sent athletes to Scotland prior to the competition.
In return, with the help of the Scottish Rugby Union, Wight traveled to Rwanda in September last year to work with a group of 20 players aged under 20.
"I really enjoyed the whole experience. It was so humbling learning about what the country has been through with the genocide to where it is now," he tells CNN.
"But most importantly the thing I enjoyed most was the attitude and desire of all the kids in showing me the willingness to learn and get individually better at rugby."
Wight says there is "a massive amount of talent and a really bright future there," though Rees admits to a modicum of frustration that she has not achieved more since her first visit to Rwanda.
"I don't want to sound negative but the potential for rugby's not been fully met there," she says, "but I'm really proud of the kids we've got playing and that some of those kids are now coaches."
Building to the future
Rees describes post-genocide Rwanda in 2001 as "still being raw, the place very basic, but the kids wanting to talk about their experiences."
She laughs at the idea that she went there planning to launch some rugby revolution.
"Football, basketball and volleyball were basically the only sports you could play then," she says. "It was a bit selfish as I just wanted access to rugby. I just taught some kids to share my passion and it went from there."
Rees and Aiken say the steady rise of the sport in Rwanda is partly thanks to Jean-Luc Barthes, the former rugby services manager for Africa at the international game's governing body.
Aiken says his death in February 2016
has "left a vacuum" but she believes that a place in the Sevens World Series in the next 25 years would be a realistic achievement for the Silverbacks.
For now, rugby continues to play its role in healing the divide between the rival Hutu and Tutsi tribes, who had previously been at war but now live as neighbors.
"Rwanda is one of the most densely populated countries in Africa," Aiken explains. "So in this whole process there's a pragmatism in that a lot of people have no choice but to move on.
"They have to build to the future, and rugby is helping with that."