Hump and Maude are from the same social class. In that case they would be a great couple but Hump and Maude both live inside their heads, especially Hump. Hump has never looked at a girl the way he looks at Maude. Before Maude he didn't have an erotic attraction to anyone, but when he saw Maude he felt one. Maude, I think, just thinks of hump as a companion and not so much a lover. I don't think she can imagine Hump and herself as a couple, but now they are stuck on an island, Endeavor Island. Now they are forced to depend on each other to stay alive. That is a perfect scenario for them to fall in love and become a couple, instead of friends.
In the beginning of chapter XXVII Hump and Maude are on a boat. Maude is asleep and Hump is thinking about how "a man would dream her the most precious thing in the world." Hump is thinking about a romantic relationship with Maude and how he wants to tell her that he loves her. While Maude, I think, is only using Hump to survive and get on land, but as soon as they see land and a little danger comes about they bond.
"Instinctively we drew closer together in the bottom of the boat. I felt her mittened hand come out to mine." P 189
I think Maud and Hump are going to become even closer because they have to depend on each other to live and when you depend on someone you tend to love them. As you see in the passage above a closer relationship has begun just by her grasping his hand. Maude seems now that she is starting to like Hump in a way that is romantic. This romance will now be challenged by their differences and the necessities of Endeavor Island.
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