Cool female lead

Contains spoilers
FL remembers her past lives
Her 18th life she meets ML as a child - they promise to marry each other but on the way to the amusement park with ML in a car, she dies in an accident at 12, ML is 9 at the time if I remember correctly
FL 19th life - she meets ML as an adult, she is super calm and I find her super elegant, her co workers all know of how amazing she is, she is known as a genius
she proposes a date to the ML on their second meeting during her 19th life