The last person Marlow sees in Brussels is

The last person Marlowe visits with is his Aunt.

"One thing more remained to do—say good-by to my excellent aunt. I found her triumphant. I had a cup of tea—the last decent cup of tea for many days—and in a room that most soothingly looked just as you would expect a lady's drawing-room to look, we had a long quiet chat by the fireside. In the course of these confidences it became quite plain to me I had been represented to the wife of the high dignitary, and goodness knows to how many more people besides, as an exceptional and gifted creature—a piece of good fortune for the Company—a man you don't get hold of every day.