Who is Andres?

O'Connell has a friend named Andres who lived in London at the time of the book's publication. He and O'Connell often discuss Existential matters, as demonstrated when O'Connell describes their conversation about a graph depicting human consumption of resources over time. Andres told O'Connell that when he looked at the steep curve of the line climbing up the page, he felt like he was going to faint.