Huh, it looks like Koharu will make the first move. Ryuu still hasn't done anything to win her over, but she's (maybe?) going to strip for and bathe with him. Disappointing but not unexpected, since "romance" in manga so often depends on women providing sexual services to men.
Weird thing about this chapter: on page 10, Ryuu gets all self-righteous in denying his new wife's attempt to dictate the terms of love and marriage to him. But he felt no compunction about telling her he was "king" in his marriage and that, "[marriage] means you would become mine, you know? Your mind and your body loving only me, living and dying for me... Marriage is that kind of contract," (see ch 8, pgs 2-4).
Which seems a far greater hypocrisy than anything Koharu has done so far.