Earlier Life
Not much is known about Blair's earlier life. It appears that he knew Crystal, as he inherited some money from her. He dated Emma Curious in his teenhood and they shared their first kiss, however their relationship was only short.
Adulthood
After his break up with Emma he meets her twinsister Ana Curious. He thinks that the sisters couldn't be more different and immediately tries to flatter Ana. But Ana, knowing that Blair is Emma's ex, isn't so sure about this all. However she can't seem to to stay away from Blair. When Emma hears about the two she freaks out and forbids Ana to see Blair ever again.
Blair and Ana decide to ignore Emma and keep dating eachother. When Blair moves in the Curious household they share their first WooHoo and later Blair proposes to her. Blair is happy when he hears that Ana is pregnant and when Kevin is born, he can't stop playing with him.
Blair finds it hard to live together with his ex-girlfriend Emma and her husband Léon. Emma acts really jealous and hits on Blair multiple times, even though Blair rejects her every time.
One strange night a fire breaks out while Blair and Ana are asleep, Emma and her husband Léon were at work. When Emma arrived back home she calls the fire station, but they were too late. Anna and Blair had died in the fire, but strangely enough Kevin was safely outside.