Sometimes spelled Calypso. The goddess who holds Odysseus hostage for purposes of sex. On the one hand, she sure is hospitable: she invites Hermes to "speak what is in your mind. My heart is urgent to do it if I can, and if it is a thing that can be accomplished. But come in with me, so I can put entertainment before you" (5.87-90) and even Odysseus says that she "loved me excessively and cared for me, and she promised to make me an immortal and all my days to be ageless, but never so could she win over the heart within me" (7.254-258).
On the other hand, she's basically keeping Odysseus as a sex captive: "By nights he would lie beside her, of necessity, in the hollow caverns, against his will, by one who was willing, but all the days he would sit upon the rocks, at the seaside, breaking his heart in tears and lamentation and sorrow as weeping tears he looked out over the barren water" (5.152-158).
Well, that's probably what he's going to tell Penelope, at any rate.