Why does Yuki like Mr. Toda?

Yuki likes Mr. Toda because he's more open about his feelings. In this regard, she compares him favorably with the unwelcome seminary students who visit her house. Mr. Toda might not live far from the seminary students at the Japanese church, but in terms of expressing his feelings he might as well be living on another planet. For Mr. Toda has a disarming frankness about him that Yuki finds refreshing. If he likes you, he won't hesitate to let you know. But if you doesn't like you, he also won't hold back.
In the midst of all the pain and upheaval that she's forced to endure, Yuki greatly appreciates such candor. In an increasingly scary world where nothing makes much sense anymore, Mr. Toda provides a much-needed sense of stability and emotional honesty.