I was going all

when I saw your update. May be I'm becoming a second Atsuko in your story lol. May be we're like them, I don't read your minds we just happen to share a same thinking

. Actually I just pieced everything you've described in your fic together to come that conclusion.
First thing first, about your chapter. Needless to say anymore, every one has already said it. Great, descriptive, and informative background on the secret contract agreed upon and signed between the two and of course, masterminded by the great Aki-p

. This man should be given award of the century for forseeing things and having great observation - as proven in your fic on his observation about Atsumina. In regards to real life events, I've always thought that Aki intended for them to have that image since AKB's debut by always putting them together and at the front, them sharing duet lines, them opening the songs, one being the captain and the other the ace - the list can go on and on, with the omission of the contract of course since I don't think he needed it. Their chemistry is an undeniable fact - even before they became best friends, and I thank Aki-p for realizing it sooner than us. It's not a forced image by any means, it just came naturally as seen by every one and I'm not even exaggerating here.
After reading it, many possibilities of where this may lead to come to my mind, but here are the two that stand out the most:
1. They did became best friends for real but it didn't stop there, it went beyond just friends and they question their own feelings. Acchan was confused, Yuko came in and it starts here.
2. As with any friendships, quarrels came along the way and since both are stubborn, cracks may happen, misunderstand may even find its way in, doubts are beginning to form, and here's where Yuko comes into the scene.
Both possibilities will display revelation of the contract, discovered by YukoI'm half hoping those two possibilities are wrong because I want to see surprises coming from you.
I think Yuko somehow got wind of the contract but blackmailing is something I don't see her doing. Like I said she's ambitious but she has pride at the same time, I don't think she would stoop that low. I can't really explain how she becomes the root to Atsumina's problem, all I can say is that - based on how Mariko described Acchan as an idiot - Yuko may have instigated something into Acchan's head, Acchan believed that without thinking carefully and somehow ended up committing some kind of actions that hurt Takamina. Her walking out of Takamina's house might be that action or the result of that action. I'm thinking this may have happened around Acchan's graduation.
Sorry for writing too much

.
And of course, thanks for updating and please update faster my curiosity can't contain anymore.
P.S.: I know right. AtsuMinaTomo is awesome awesome threesome/friends/combos whatever you want to call them. They're my favorite 91ers in AKB too, like how all three joined AKB when they were 14, being best friends, being 1st original members, being seen as the future of AKB, both Acchan and Tomochin have said they love Takamina

, Takamina has said both are important to her, and coincidentally, both decided to graduate before her

(I hope some day both will come back and bring her with them). I love them a lot and I've said this already on another thread, that Tomochin is the only one whom I approve of getting in between Atsumina because TakaTomo and AtsuTomo are just as awesome as Atsumina. I'd be ecstatic if you include more AtsuTomo/TakaTomo in your fic.