well eh finished this on dec 8, 21 and the author did a great job of showing his intentions of making the story bittersweet, it's cool the friend or lover kinda conflict and well yeah life is a series of choices and wether we made the correct choice or not doesn't really matter because at the end we will always face a consequences and of course there will be problems arising in difference, we can't always avoid and pretend nothing happened... it will come either ways since it's inevitable... but that doesn't mean you just have to choose whatever without thinking things thoroughly- just like what this manga suggests, choose the choice that you think is best, you may regret it or not in the future but in the end that was what you thought was best... I'm going around in circles i wished i can phrase it more better... but anyways, at the last chapter (not the afterwords) it was pretty obvious that it was touma but still the author did that first perspective thing the least i had expect was to see both of them all grown up and happy, showing their engagement rings...
Ao no Flag