Charlie was holding a Healing Pill in his palm at this time.
The Healing Pill was about one centimeter in diameter, and he did not bother to put it in a wooden box because it was not as precious as the Rejuvenating Pill. Instead, he simply sealed it with wax paper specially used to seal food.
When Kathleen heard that Charlie was going to give her a gift and was acting like a child as he deliberately clenched one of his fists with his palm down as if it was a mysterious gift, she thought that