So ... This is Sulfur, with his fiancee Mekkan. Their marriage was arranged by their parents, much to Sulfur's chagrin. But Mekkan, on the other hand, was ecstatic, since she always harbored feelings for the man.

Mekkan, upon hearing of the incident when Sulfur saved Kimiko's life and now has to stay with him to repay his debt, becomes bitter toward Kimiko. But she's still a generally kind person.
Just a little jealous.

Sulfur never intends to go through with the marriage, but he and Mekkan are quite good friends, or, at least, the closest thing Sulfur has to a friend.