This may be a stupid question but I don't know the answer!

Kingdom Hearts 358/2 Days.

Ok, "Kingdom Hearts" is the game name; "358 [..] Days' is the number of Days that Roxas spent in the Organization XIII; but why "/2"?
What does the number "2" and the "/" are doing there?

And when you speak the game you usually call "Kingdom Hearts Days", but if you're saying the full name you say "Kingdom Hearts three hundred fifty-eight bar* two days"?

*I do not know the name that english language gives to "/", in portuguese we use "barra", so "bar"?

I think this is a great example of Noruma trolling his fans.

For me

at first, when I beat the game, I thought that the "/2" mean that it went "over into Kingdom Hearts 2", since it ended on The First Day of Kingdom Hearts 2. Yes, I realize how stupid that sounds, but that was my first reaction after beating the game. The "/2" may also mean the days he left the Organization before he was taken by DiZ.

I initially read it as "three hundred fifty eight and a half days" but come to think of it that doesn't make much sense. From looking it up really quickly, it might have something to do with 358 days through the eyes of 2, aka roxas and xion

I thought the "/two" was to symbolize its status of stretching into the timeline of two things.

Roxas's days in the Organization, and Chain of Memories, since they happen at the same time.

I, due to habits, pronounce it "Kingdom Hearts 358 and a half Days", I'm not sure why. I believe it's just because of how it's written and because I've been taught that a number with a /2 after it means a half most of the time.

/2?

At first I thought it was because Xion and Roxas were sharing powers and Sora's Memories...

But It IS true, that Xion doesn't live the whole 358 Days. Only 351-ish.

So maybe it's between Roxas and Sora?
They share memories, and their Keyblade. (The keyblade Roxas uses in Days and the one Sora has are the same. but since Sora was asleep During most-The whole time they didn't over lap.)
(and yeah, I know up until day 28 both use it at the same time, but Sora was using Kingdom Key's CARD. not the actual thing, it may be possible...)

Sora wrote:/2?

At first I thought it was because Xion and Roxas were sharing powers and Sora's Memories...

But It IS true, that Xion doesn't live the whole 358 Days. Only 351-ish.

So maybe it's between Roxas and Sora?
They share memories, and their Keyblade. (The keyblade Roxas uses in Days and the one Sora has are the same. but since Sora was asleep During most-The whole time they didn't over lap.)
(and yeah, I know up until day 28 both use it at the same time, but Sora was using Kingdom Key's CARD. not the actual thing, it may be possible...)

Or I think that it's because it was mainly about Roxas and Xion (just my personal opinion).
Either that or yeah, because it branches into KH2.
Then again, it could also be because it shows the origins of the friendship of Axel and Roxas and how it developed, but i think that's the least likely reason (again, in my opinion)

I thought it was because two days didn't count for zion nor roxas, being as they are nobodies so they may have had two extra days and a half to be completed? not sure, but thats a good question.