Asami is 35 at the beginning of the series, Akihito is 23. Asami does not have a brother let alone a twin (at least not one that has been introduced) nor do we know anything about his family. Akihito's parents are apparently still alive as he tells them goodbye in the Hong Kong arc when he thinks he is going to be killed. Their current ages have not been stated, not has the actual time they have known each other been indicated. Hope that information helps.
Were you confusing the canon manga with fanfics? Or perhaps another series? (almost sounds like Junjou actually. Would make sense if you confused Asami and Usami...) Also would like to add that there is no news of an anime being made and probably won't be considering how old this series it. There's only the animix and drama cds.
I think viewfinderr the way the story is written is absolutely beauiful one thing I just wish they make it more like the cartoon animate hard to try to read all those books I do have a question? how old is asami and his brother are they twins are they a couple years apart and if I'm going to start reading the so many different versions of the story I'm getting confused are they going to make more cartoons and animation like the first one I love it I can understand it better than his brother find stuff out there right what if they could take this as actually you'll be able to sit down or talk with them awesome technology for god sake use it fangirl the writer of this story girl you is a bad thing please don't stop writing I please have this way the too a cartoon just like the original while looking at please girl you in 2015 happy new years to you please make it so that isn't English subtitles I am an English person I speak English so please subtitles in English so I can understand it girl you got a hell of a book it is f****** gold can you imagine fan girls if you able to action sit down with the. Anime cast of view finder anime 3 d and 7d has anyone seen this incredible seen on youtubePS keep up the good work girl who knows who knows