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My guess would be the ones like the firework extra or the one in the onsen did really happen...The stuff with the office on the other hand seems more like a crack AU, especially since one of them is clearly said to be only Akihito's dream. :)
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Fireworks did happen because if you look at the map of Asami's condo, there's a heart there which is a symbol of where they did it.
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Sorry - there's a heart of the balcony.
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I've been wondering did the threesome actually happen?
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Well, the bit with the office was a dream, but I'm pretty positive the part where Akihito handcuffed Asami was very real. ;)
As for the threesome, by instinct I'd say it happened as well...If you're looking for proof, maybe the beginning of the chapter is a hint - It started out with an explanation why Akihito was working at that onsen which tried to tie it in to the main story. That would be pointless if the scene wasn't supposed to be real. :)
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It looked more like "except with Feilong" rather than "especially not with Feilong". xD Somehow I can't imagine Asami allowing the same thing with, say, Mikhail or Sakazaki... I think he let it happen for one, like you said, because Akihito teased him as well, and for another perhaps because he was curious about what had happened in Hong Kong. Anyway, I didn't mind it ^-^
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The end of the threesome bothers me because of how crackish it seems with the Russian mafia showing up and no danger appearing afterwards. Seeing as Mikhail's back in the story, we should soon learn if Yuri is actually alive or not. If he's not, it's proof that it didn't happen. If he is, it's back to everyone's opinion.
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It is kinda crackish, but I still laughed my butt of when Mikhail showed up xD Well, maybe there was no danger because Mikhail's focus at that time wasn't on Asami or Akihito...maybe he followed SOMEONE else. *wink wink* x)
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Well, if Mikhail came there for Feilong it kinda makes sense that he didn't pay Asami and Akihito any attention. ;)
Guys i want to ask about the extras like the firework one ? they did happen or not like the office ons that aki is the boss in it ???