So is there one main character? I mean it doesn't have to be all about him/her but some mangas with many characters become disjointed for me when there is no one really to rally behind. Or is this manga capable of having many characters and not becoming a mess.

Thanks in advance.

Sort of, the main characters are pretty much Hana and Natsu. You usually switch between their perspectives, and occasionally the perspectives of those around them. Now and then there are side/back stories from the perspectives of completely different characters (these always tie in to the main plot line of course), but in general, the manga will always come back to either Hana or Natsu. So yes, I believe they are the "main" characters in the loosest sense of the word. Though I do know a lot of people who hate either one or both of them, so it's actually a relief to switch out of their perspectives sometimes. X3 I personally love all the characters (though originally I wasn't fond of either H or N), so it all works out fine that way too.

Plus every character gets to have their own little moment of development (some more so than others), though it never gets tiresome or tedious, nor do you ever feel like you've been loaded with too much information. Every character is clearly distinguishable from the rest, so you won't get confused as to who's who either (though you may forget their names at first).

I don't believe this series has become a mess yet, and it's 20 volumes in, so I think it's safe to say that the manga artist knows how to keep everything together and keep the momentum driven with a solid plot line despite having to juggle a massive cast (and multiple branching plot lines). I am super biased though because I just adore this series and the manga artist, so don't take my word for it. But I do know how hard it is to follow series with too many characters, especially when the manga artist is in over their head and doesn't know what they're doing. But I do believe Tamura-sensei has it completely planned out, and she knows what she wants for each of her characters. I think that's what sets her apart from all those other manga artists.