Let's see, probably Jin = Ragna Nu = Ragna Noel = Ragna Rachel = Ragna Platinum = Jubei (Duh.) Tao = Just wants to eat Makoto = Just friends maybe? Litchi = Arakune (Duh)
Noel is seriously not the kind of girl to be running around without underwear, especially not in a one-piece dress that's more of a SHIRT than anything with a skirt (and especially not considering her Muzzle Filter attack). The art team just likes to tease us with ass-shots of her and Platinum.
But yeah, Noel was important enough to Makoto that Makoto betrayed the NOL for her sake, despite the fact that she joined the NOL in the first place for the sake of her large family. So, Noel is at least as important to Makoto as her family, and possibly more so. (Noel's two normal foster-parents had to go into hiding. Hiding a big family of squirrel-people is going to be hard.)
Makoto was also willing to kill Tager if he brought Noel to harm, which would have made her an enemy of Sector Seven. Thus pissing off the OTHER world super-power and leaving her and her family quite screwed.
Plus, given her cryptic comments to Tager regarding cloning, and her interaction with Lambda, I'm quite sure Makoto knows Noel is a clone and Murakumo unit.