During the 2012 London Olympic Games, Millousi competed all-around in qualifications scoring a 12.800 on vault, 13.425 on the uneven bars, 14.366 on balance beam and a 12.933 on floor exercise for a 53.524 all-around score. She failed to qualify for any finals, however, her very respectable 14.366 on beam placed her 18th on the event and due to the two per country rule made her the 4th reserve for the beam final.
2013-2014
In 2013, Vasiliki competed at the Cottbus World Cup and won the silver medal on beam. She also competed at the Mediterranean Games in Mersin, winning a bronze medal in the team competition and a silver medal on beam giving her a total of four Mediterranean Games medals. Millousi also competed at the European Championships in Moscow where she chose to specialize on beam. She did not make the finals however, after a fall on beam meant she scored only 12.666. Millousi then went on to compete at the 2013 Antwerp World Championships. In the competition, Millousi performed well on vault and floor however, a mistake on beam and multiple errors on bars caused her to finish in 24th place with an all-around score of 49.532. In 2014, Millousi began her season competing again at the Cottbus World Cup, though failed to make any of the event finals after errors on bars and beam in qualifications. Next, Millousi went to help out the Union Haguenau team at the French Championships Team Final by competing on bars, beam and floor. After two unsuccessful competitions, Millousi competed at the Korea Cup where she rearranged her beam routine. She won the gold medal on beam with 14.325. At the 2014 Nanning World Championships, Millousi rearranged her beam routine and in qualifications, had a strong performance scoring a 53.933 all-around - just missing out on the all-around final by 0.309.
2015-2016
Millousi began the 2015 season by once again competing at the Cottbus World Cup. She did not make the beam final after only scoring a 12.466 in qualifications after an error. At the European Championships in Montpellier, Millousi made an error on the uneven bars and did not qualify to the final. After her disappointing European Championships, Millousi competed at the Baku European Games where she qualified to the all-around final. Next Millousi competed at the Hungarian Grand Prix, winning the gold medal on beam and the bronze medal on floor. Millousi ended her season with a disappointing performance at the World Championships in Glasgow performing on three events. In 2016, Millousi first competed at the Doha World Challenge Cup where she qualified to both the beam and bar finals. Millousi was 5th in the bar final and was on track to win another World Cup medal on beam until she crashed her double pike dismount to finish in sixth place. In order to qualify for the Olympic Games, Millousi went to compete at the Olympic Test Event in Rio, performing well and scoring a 54.431, allowing her to qualify for the Olympic Games in Rio. Millousi then went on to compete at the Greek Championships winning the beam and floor titles with a 14.500 and a 13.650, respectively. At the Bern European Championships, Millousi submitted a new skill to the judges - a switch split leap in a stag ring position.
She competed on the balance beam at the 2016 Summer Olympics where she wisely decided to change her double pike dismount to a gainer layout dismount. She finished in 57th place in qualifying after falling on her aerial cartwheel and did not advance to the finals.
2017
Millousi competed at the Greek Championships in March where she placed third on uneven bars and second on balance beam. She later competed at the Baku World Cup where she won the silver medal on balance beam behind 2004 Olympic ChampionCătălina Ponor. In April she competed at the European Championships but failed to qualify to any event finals.
2018
In June Millousi competed at the 2018 Mediterranean Games where she helped the Greek team place seventh and individually she placed fifth in the balance beam final. In August she competed at the European Championships. She qualified to the balance beam final and finished in eighth place. In October Millousi competed at the World Championships. During qualifications she placed 32nd on balance beam and did not qualify to the event finals. She announced her retirement shortly after, officially retiring on October 30, 2018.
Personal life
Millousi has been in a relationship with fellow Greek gymnast Eleftherios Petrounias. On June 16, 2019 the couple announced they were expecting a baby. The following month the two were married.
