With the recent reveal of cortana in the television series, fans have naturally criticized the new design for not looking as faithful Well there's actually some explanation for it, and it's kind of weird. This is has lead to a counter backlash of criticism for the criticism stating that cortana's nude appearance was always just fanservice, something voiced many times before.
Okay, so maybe i'm being a little hyperbolic about it being the strangest mystery in all of halo, but the question remains
Well, we had to ask franchise director frank o'connor:
Halo franchise director frank o'connor has offered an explanation as to why master chief's ai companion cortana chooses to render herself as a nude woman. Halo fans have long wondered why master chief's artificial intelligence buddy cortana looks like a naked (or at least mostly naked) woman Franchise head frank o'connor gave the official.