I'd honestly guess because it's fun to draw.
(Hanamaru's right on page 9-10, by the way — replying to "wait a minute" with "So you really don't want to be with me?" isn't fair, zura. I'm okay with it here both because it doesn't seem intentionally manipulative and because fiction, but hitting the "oh, I guess you hate me" button right after you try for something your partner isn't sure they want is kind of a coercive gesture.)