The Captive Sea Daughter

Annica, a young mother and widow in a beleaguered Norse village, was convinced this was the only way to protect her young son and her people against their encroaching neighbors. It was a seemingly absurd plan by her father-in-law, the chieftain,  but she was desperate to save her son so he may live through more summers. 

She takes the silver necklace from the chieftain, who claims it is a gift from a witch that would grant her the powers of the Rán and help save those she loved from destruction. Steeling her resolve, she puts on the artifact around her neck, which quickly enveloped her whole body in 

Waking up, she discovers to her horror how her legs have been replaced by a long silver fishtail and the power to enthrall anyone with her enchanting voice. But worse still is when the chieftain finds her and gone is the barely familiarity on his face that he once had for his daughter-in-law, replaced by cold contempt as he reveals a silver bracelet that her necklace is bound to, with which his commands are hers to obey without question. With this he controls Annica, now a daughter of Rán, to do with and use as he pleases.

=====

Commission for anon, based on a story they wrote with the theme of mermaids being completely helpless and at the mercy of men while on land.