@Adam Whitehead: Your logic is sound Adam.
I am hoping that the Others are the reason they kept dragons around in the first place. I guess if they waited for the Others to over-run the North, Jon Snow and Bran wouldn't make it to book seven.
@Starwatcher: The whole theme was "loss of innocence". You don't get that from holding hands! It seemed pretty clear to me that they had to get intimate to save the universe.
Then of course, like all the relationships in this series, they had to be separated and unhappy forever after.
@RandomFrequentFlierDent: Stephen Baxter's The Time Ships is another good sequel to The Time Machine. Baxter's Morlocks are the engineers that keep the world working for (or in spite of) the frivolous Eloi.
@kagekiri: How about the angel sent to destroy Jerusalem. "Then David lifted up his eyes and saw the angel of the Lord standing between earth and heaven, with his drawn sword in his hand stretched over Jerusalem." That's a badass angel.