[Krono]

Originally Posted by aohige

It's really the volume and impression.

There's so many canon pairings of other main characters, that Shiroe himself's situation is less focused and trivial.
Pretty much every other prominent guys and gals gets a mate.
It also helps that while Shiroe is the protagonist, Log Horizon leans towards the nature of Ensemble casting with less focus on the protagonist.

We shall see if that's enough to keep people from calling it a harem. I'm not optimistic.

Spoiler:

Especially given things like that "unofficial general info" crap reposted from 4chan. Bashing SAO while talking about how LH isn't a harem as one of the "comparisons" is pretty much begging SAO fans to start calling LH a harem the moment Shiroe hits three girls obviously attracted to him. It also builds people's expectations that the number won't rise above one girl attracted to him, lending to the possibility of people that would otherwise not be bother much remarking upon it specifically to counter the misleading information.

Originally Posted by tsunade666

Even so, I think its more likely a Shiroe and Akatsuki pair.

Be that as it may, SAO having a definitive pairing does not stop people who have seen the full series from still calling it a harem. As such I'm not optimistic about LH with less definitive pairings avoiding the term.