Heart Hot Water Bottle

Containers for warmth in bed were in use as early as the 16th century. The earliest versions contained hot coals from the dying embers of the fire, and these bed warmers were used to warm the bed before getting into it.
Even though their use has largely died out, they remain very popular  in the United Kingdom. There has been a recent surge in popularity in Japan where it is seen as an ecologically friendly and thrifty way to keep warm.

If your lady has feet as cold as ice, then this might be just the warm-hearted
(footed?) gift she’ll love!