Our first mention of Segur is Nina’s declaration that he’s "around somewhere" with Ferdinand in Fialta.
When Segur finally approaches Nina and Victor (alongside Ferdinand), Victor describes him as "a lover of art and a perfect fool." He goes on to say that he can’t imagine why Ferdinand keeps him around.
Victor remembers Nina once exclaiming that "[Segur] is such a darling," but he feels this doesn’t "commit her to anything."
Segur starts complaining about the weather, which confuses Victor, who finds it a useless topic of conversation.
Segur stops with Ferdinand at a post office, leaving Victor alone with Nina.
When Nina and Victor stop by the yellow car, she informs him that it belongs to Segur.
Segur and Ferdinand approach after Victor has his premonition by the car.
We go back in time to the lunch that the four friends shared earlier that day; afterwards, Segur goes off with Ferdinand to make a phone call.
After Victor awkwardly declares and then retracts his love for Nina, she leaves in the car with Ferdinand and Segur.
Victor finds out later from reading the paper that the yellow car was in an accident. Nina was killed, but Segur and Ferdinand escaped with only minor injuries.