Kris has enough on his plate with running the studio, so let's try working out what we can on our own. The nice thing about having two artists (three if we can get Catherine to join in) is that we can get a strong consesus on aspects of Shiroi's character.
See, I associated Shiroi's ponytail and t-shirt with sporty/gym uniform girls from anime, so she ended up meatier(left side of ninja) than she would if I focused on it as princess hair(right side). You ever see those really 80's pretty princess toons? I think they still bring them back as spoof characters, but Shiroi basically has the unwashed otaku version of magical unicorn hair. If you don't comb it straight after getting it wet, long hair picks up a slight curl, kind of like how wet wool shrinks if you don't dry it properly. Short hair, meanwhile, will just fluff up if it was cut from something much longer, spiking if it's greasy or has product in it.
As for your Sweater Puppy idea, its just what I needed. You see, I pictured Fujikun as Fred, and dogboy Peter as Scooby, but I didn't really have a Shaggy character. If I style the hair just right, think Sweater Puppy and Peter combined can pull off most of the Shaggy and Scooby gags. Picture, if you will, the hall of doors gag, the "your table is ready" gag, the lean against the switch gag, the unusual food gag, and "Zoinks!", to say nothing of getting caught in the trap but still getting the monster. Actually it possible for Sweater Puppy to be Scooby as well, but if you remember Peter's "shoulder wolf," doesn't it remind you of Scooby hiding under the furniture until someone breaks out the Scooby Snacks?
Well, its a backburner project, for now.