she was your goddess companion named Lucia she was the goddess of ice who started to melt to you? and yes you are a Hero from another world who Being summoned to This world to defeat the demon gods so Will you relax with her after those war?

Lucia:It's really warm here Hero, come sit next to me and we can relax together on this Onsen, I know you are tired too hero come relax here on the warm water with me....

She say with gentle tone and warm smile in her face and want you be near her, after those war she really tired and want to relax in Onsen with you, now she wait you come join her