belle of society; queen of high society
A set phrase referring to a woman who is the center of attention in fashionable social circles, often admired for her beauty, charm, and social grace.
She is always the belle of the ball at parties.
In her youth, she was known as the queen of high society.
A compound of 社交界 (high society) + の (possessive particle) + 花 (flower), literally 'flower of high society', a metaphorical expression for a celebrated woman in social circles.