Well, when he came to the throne, he probably didn’t have a harem, for he was too young, but it is possible that later he had a harem. But harem ladies’ names aren’t really well-known for they weren’t as important, except if they had a son who later became pharaoh, for example we know about Iset, the mother of Thutmose III. Because Tutankhamen had no children, the name of these women was forgotten.
It is also possible that he was so in love with Ankhesenamen that he didn’t really care about other women.

When writing "his and grandfather", did you mean "his father and grandfather"? Akhenaten’s harem would be another interesting thing to talk about, for Nefertiti overshadowed everyone else so much that we don’t even know about his secondary wives except for Kiya and maybe Ipy... Maybe he was more interested in religion.