The Question and Answer section for A Long Way Gone is a great resource to ask questions, find answers, and discuss the novel.
As in the previous chapter, Beah uses a flashback here to fill in the missing years between his induction into the Sierra Leone army and his transfer to the UNICEF compound. Whereas earlier flashbacks were of better times with his family (which...
I think that would be Esther. Esther is the nurse at the UNICEF compound where Beah convalesces following his escape from the life as a child soldier. She attempts to win Beah's trust by patiently showing an interest in him without pushing him.
The first mention of the drug can be found on pg. 116 of the text.