What family story does Dilip tell when he announces to Antara that he wants to be a vegetarian and why does he tell this story?

Dilip tells a story about his father's aunt Kamala whose father beat her and locked her in a room when she said she wanted to be a Jain num. Kamala plucked the hairs out of her head in honor of Paryushan. Dilip tells the story to show Antara how he comes from a family who has always had a calling "for radical non-violence" (56).