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From Anime Waves:
Nakabaru Taiyo came to Okinawa in the pursuit of beautiful ladies and the blue sea... But while trying to hit on a cute girl, she told him that her mother hated him... And then a wonderful story of scuba diving, beautiful women and adventure begins!


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Latest Release(s)
v.10 c.55 (end) by AnimeWaves over 14 years ago
v.10 c.54 by AnimeWaves over 14 years ago
v.10 c.53 by Anime Waves over 14 years ago
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in Country of Origin
10 Volumes (Complete)

Completely Scanlated?

Anime Start/End Chapter

User Reviews
IO by Master_M2K

2 topics, 21 posts
Click here to view the forum

User Rating
Average: 7.7 / 10.0 (507 votes)
Bayesian Average: 7.63 / 10.0

Last Updated
October 26th 2020, 2:15pm PST



Category Recommendations





Original Publisher

Serialized In (magazine)
Young Magazine (Kodansha)

Licensed (in English)

English Publisher

Activity Stats (vs. other series)
Weekly Pos #617 increased(+106)
Monthly Pos #1580 increased(+124)
3 Month Pos #2705 increased(+185)
6 Month Pos #3668 increased(+371)
Year Pos #4350 increased(+1036)

List Stats
On 546 reading lists
On 589 wish lists
On 1546 completed lists
On 81 unfinished lists
On 210 custom lists

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User Comments  [ Order by usefulness ]
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luv them all except one  
by kevs926
October 10th, 2012, 8:04pm
Rating: 10.0 / 10.0
i like all the girls except Mar. Why is she a poor girl? trying to win the Love battle by having Taiyo's sympathy, her character is pretty unimportant. It shouldve been just Lago, no need for Mar.
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Mangaka ruined the plot in the last several chapters  
by TheGentleman
April 24th, 2012, 1:16am
Rating: 5.0 / 10.0
It was a great story but literally there were ruining moments like with what Mar says happened as a result of Taiyo. BTW She likely lied AGAIN, notice all the lies she said about what their relationship was between them when you read it. Also remember Mar & Lago are half sisters with different mothers<- ehm who is the father of Lago cause that is the same father of Mar confused confused before you attribute said burning sensation to result of action listed above. She carries the blood too.. so the thing that she said happened is a lie.... oh look ANOTHER LIE. Oh and the letter, prorpbably just letting T know hows she is doing now, M just grabs it so S doesn't find out something happened (with no result) with a person in another place(Mar). M is saving T from getting his ass beaten by S, over what happened.(there was no result) S was pretty jealous after all, and M promised to keep it a secret. That would carry over. Again no indication of a result at all.

nail80 you pretty much said it, especially about the affair piece. There are a lot of other parts I can forgive but that ruined the story. The worst part is there is no actually indication of a result, its just implied and Mar lied so much that I don't believe that even. ( the letter is non-conclusive) The plot before the last 3-4 chapters was good so I'll give a 5/10 but I was happy reading this and then it made me just angry. Why was the mangaka such a moron?

Oh, don't care about Taiyo''s father. Everything is pretty much his fault. But to actually put the affair piece in to make Taiyo look like scum was trashy by the mangaka.

... Last updated on April 24th, 2012, 1:27am
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Mystery at Its Best  
by Seijurou
December 17th, 2011, 10:53pm
Rating: 8.0 / 10.0
One of my favorite manga. Beautiful, engaging, mysterious, and exciting, this story takes you by the necktie and does not let you go until the end; you always end up wanting to know more:
  • Why does a strange girl tell the protagonist that he killed her mother?
  • What is the strange mark on the little girl's chest?
  • Where does the white whale come from?
  • How come he does not remember going to Okinawa before?
  • Will he be able to find his missing father?
  • In which way do the girls relate to him?
  • When did he meet them before?

Cliffhanger galore.
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by TRMshadow
July 9th, 2011, 9:33am
Rating: 1.0 / 10.0
One of the most God awful pieces of human excrement I have ever read. The mystery/supernatural element of the story was uninteresting, with each character I feel like I've met this person before, and anyone with even the smallest sense of decency will agree with me that
Spoiler (mouse over to view)
knocking a random girl up and then dumping her (along with the child) is not the way the world should work. Not to mention not even telling the girl you were originally with acting as if nothing happend!!!

Truly one of the worst stories I've ever read in my half-decade of reading. Absolutely atrocious in ever single sense of the word. Never before had I literally felt ill after reading a manga..... now I daily suffer with a horrible experience I'll, as hard as I try, never forget.
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Flawed but entertaining  
by connerity
February 6th, 2011, 10:44am
Rating: 8.3 / 10.0
It had a very good buildup of the mystery until around chapter 40-45. After that too many new things were introduced towards the end without resolving every issue, creating plotholes.
That's basically why I didn't like the ending, would have needed either less chapters and less "new" plot elements introduced in the very last chapters or would have needed about 10-15 chapters more to bring everything to a proper closure.
The author also made people look much better than they really are, especially taiyo's father.
Spoiler (highlight to view)
Due to Taiyo's father being an ass, the harem ending with all 3 sisters was ruined, would have worked out much better imo, I feel especially bad about Mio, she was a much more interesting character than Shibuki.

Nonetheless, it was an entertaining read, recommended if you like light mystery and light love stories.
Honorable mention goes to the art style, everything looks more real than most mangas, especially the girls, not everyone has a model or typical manga body and face, they look like more like real people, everyone has their flaws.
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Not a good read but not a bad read either  
by thischinksays
June 4th, 2010, 10:32pm
Rating: 7.0 / 10.0
If you've got time and you're bored, give IO a try. The art style is a bit awkward at first but it definitely grows on you. It can be a bit confusing and convoluted at times but it was still an enjoyable read.

Spoiler (highlight to view)
I really wish that the mangaka hadn't ignored Mar towards the end. She definitely deserved to show up again, being the best character in the manga and all. This was what made me mad during the end.
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Plot holes and flaws but keeps you reading  
by Druid
February 7th, 2010, 12:15pm
Rating: 6.0 / 10.0
Most people have already said what I would say so I'll keep this short. What I dislike most about this manga is how some of the characters do some absolutely horrible things and yet the main characters seem to sympathize with them. I won't spoil the story with examples here (read my post in the forum topic "IO The Ending" for a specific example) but if you read through it all then really think back on it, these actions are really unforgiveable.

That aside, I did read this from start to finish and the truly bad mangas are the ones that can't keep me interested so I can't give this a truly bad rating. Just know that there are some characters you're going to want to at best beat upside the head (Taiyo for one), at worst (I know she dies) throw in a jail cell for the rest of their life.
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by jackblack901
November 13th, 2009, 3:07am
Rating: 8.0 / 10.0
I agree with most of ppl comment here, the story did not reach it potential. It build up quite a deep and interesting mystery, but somehow it was not solved well in the end and leave me unsatisfied, i don mean it really bad, it's quite a lot of details in the couple of last chapters, it's just lack of something.
About the harem twist, it's really light in the beginning and most of the first half of story but then it suddenly went out blue and even become a bit creepy and complex. And it does not solved well neither.

Anyway, it was quite good read, it's worth my 6 hours reading at least. I think the biggest problem it deals with a lot of genres: drama, mystery, harem, rommance, ecchi, supernatural also a bit tragic and comedy... all of them became good part of the story but none of them can go above average.
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by kidsoshi
November 10th, 2009, 4:19pm
Rating: N/A
i enjoyed reading IO. it was very entertaining and left me wanting to read more. i recommend it. the characters and the story were good. but is it weird that i was rooting for mio? cuz when the ending came i was devastated lol. it was a very good read.
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Roller coaster of enterteiment  
by chulian1819
June 11th, 2009, 7:17pm
Rating: 9.4 / 10.0
I liked a lot the story telling, the technical facts and the detail of scuba diving (reminds me of Beck with the guitars bigrazz ) and also lots of details in the machines, vehicles but sadly this details sometimes lacks in the girls sad sometimes the drawing of the girls looks weird dead but something that I liked of the girls drawing was the bits of tummy fat thats makes the girls look more real than fic biggrin

For the boys (like me) lots of bikinis over beautiful girls n///n

Has lots of parts action packed, has its parts full off love love <3 and others just fun with the girls ^^

Lots of mixed feelings but over all great read, made me stick till the bitter end bigrazz dont regret reading it wink

... Last updated on June 12th, 2009, 5:58am
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