Ah, now I know why I subtly feel uncomfortable about Kiel. He ignores the possible burdens he's mildly forcing onto Marie "for her own good". (Eating well, protecting her- luxuries that may cause trouble that would further need her to rely on him to clear up). Or even not for her good, just under the excuse of being close friends. Saying they're close friends, but still being a tiny bit flirtatious or ambiguous with people who might misunderstand. It's very subtle, but I can feel a sort of second-hand discomfort.
Not that I like the crown prince necessarily better or anything, but...