A couple of things. I read the title as Vividred as in Vivi Dread and was quite disappointed when I learned it was as Vivid Red instead.
And poor Momo, who wants to help her sister, but wasn't born with bluish, greenish, or blondish hair with bluish, greenish, or goldenish eyes and wasn't in need of help when an Alone attacked. Well, needing help while an Alone attacked might be optional, but I guess it would help seal the deal. Unless they add violet or cyan or magenta or whatever, though she probably would have to dye her hair and get contacts or something.
Also, one has to wonder if blue/green/yellow can only dock with red, or if blue can dock with yellow while red dock with green, and if so, can the docked blue/yellow dock with the docked red/green.