She gave Mikado the elixir of life, as she couldn't bear to hear of his death and was hoping to meet him again so they could have a good life together. Her adoptive parents already had a good life together and that's why they didn't receive the elixir.
We can arrive at this answer because:
Hoping to see her lover again, Lady Beaming Bright gives Mikado the elixir of life so that he can stay alive and they can live together one day.
This tale shows how a divine being in love can try to change the nature of people so that they can achieve their goals.
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https://brainly.com/question/116804