Shizune's route held a lot of frustration for me - mostly because of friggin' Misha ruining the secret sign language Hisao is picking up. You think about a girl who's a deaf-mute her entire life, and even with the mode of pen and paper and signing, she has to have some difficulty expressing herself precisely. Particularly with how Misha is always bubbly, it's like everything she does goes through a filter. Here's Hisao, then, working his tail off to learn sign language to engage her on the closest terms he can, and Misha goes and spills the beans before he's ready. Like I said, frustrating.

That said, it was still a route I liked a lot, though the ending felt strangely empty. Aside from Hanako's route, I feel like Shizune's involved the most accommodation to her disability. With the aforementioned connection they establish by breaking down those barriers of communication, it makes the whole process of getting to know her that much more meaningful, I think.