Arianni left her clan to pursue a romance with an Antivan merchant, Vincento. The affair was passionate, but ended the moment she told him she carrying his child. He left her, saying that he had urgent family business to take care of in Antiva. Her clan refused to take her back in because of her human son, and she was forced to live in Kirkwall's alienage instead. Sympathetic alienage resident found her a job washing linens, and she managed to raise Feynriel on her own despite their poor circumstances.
Though she tried to hide his parentage at first, she eventually had to explain that he would always be an outcast thanks to his human-elven heritage. Feynriel was full of questions about his father and Arianni tried to reach out to Vincento again. She received a curt reply from him, which overjoyed Feynriel.
When Feynriel was eight years old and she realized he was a mage, Arianni refused to send him to the Circle, and instead kept his abilities hidden. As a Dalish elf, she'd been exposed to magic daily and believed she knew enough to teach him how to control and hide his new powers. This worked for a few years, until it became apparent that Feynriel was no ordinary mage. When his nightmares became more severe, she contacted Ser Thrask, whom she knew to be sympathetic to mages, causing Feynriel to run away.
The three possible outcomes of the quest, Night Terrors, determine her fate.
- If Feynriel lives and chooses to flee to Tevinter to master his powers, she moves to settle with the Dalish at Sundermount. If spoken to, she states that she should have returned to her kind a long time ago and is happy for her son, though she misses him.
- If Feynriel is killed in the Fade, whether at his request or under Hawke's command, he becomes a Tranquil, now residing at The Gallows. She commits suicide by poisoning herself, justifying that she would rather die than see her son a Tranquil.
- If Feynriel is possessed by Torpor, she comes to despise Hawke. Marethari defends Hawke, saying that none are immune to the temptation of a demon. Regardless, she loses respect for Hawke and is never seen again.
- (After sending Feynriel to the Circle) "He may never forgive me for sending him there, but I'd rather him alive and furious than dead and buried."
- Even if Feynriel was made tranquil and Cullen says she committed suicide via poisoning she may still be found (and potentially killed) in the Dalish camp.