In this last chapter of “The Rhyming Little Mermaid,” Serena finds herself in a strange, white place in what appears to be her own little room and is surprised to find that her feet no longer sting and she can sing. As she steps out of her room, she hears a voice that fills her with joy and beckons her closer. The voice belongs to someone who knows all about her suffering and offers her a chance to start anew.