On the other hand, Kanako and Touko do tend to be pictured together, regardless of wether it's in-character. Also, she's looking back sort of nervously at Touko, which seems more like something Kanako would do.
Notice Sachiko has her split on the left side and keeps the forehead hair /short/ and combed straight down to the side (post #47520), where as Kanako keeps hers /long/ and splits it in the middle going the ^^-type antenna look, which can still be clearly seen here (post #18877). In this image she's just combed/drawn with her usual dangling front tails behind her back/ears.
