With Yumi, it was more of a conscious choice for her to be a little distant in her replies, as opposed to Suishou and Sakura. Since she's being an emo kid to the max deep down in her soul, or whatever. Although I certainly know there's a fine line between being distant and just being impossible to respond to. So, like I said to the anon above, I'll keep an eye on it. (Also, usually when a character is pointed out as being generic, I freak out and get hyper-attentive to all my characters' replies so haha sob.)
I'm sorry if I've been impossible to tag back lately. 8(