"My birth mother was a human witch my father dallied with during a summer he spent on land. She gave me to him to raise after I was born with a tail." As far as Ulla knows, she's the only half-human to ever come of sildroher dalliances on land. And she trades shapes often enough here, but she grew up underwater.
"I never met her. My human half brother sought me out once we were both grown, and told me what I was. But there had always been rumors. I never quite fit."
She studies him a second. "Did you have a hard time of it because your mother was your father's mistress?" Because he said it like that mattered a lot.