the whole dialectic in the comments is basically "oh no, he's coercing/manipulating her, that's bad" vs "no, he's just 'setting boundaries'". both are wrong. the term "setting boundaries" is always equivocal and dishonest, trying to frame something as neutral or equal which is always unequal.
he's coercing her, pushing her to submit not just to this demand, but to future ones, and to proactively please him. but that's good. it's objectively what sexuality is all about between a man and a woman. it's the path of happiness for both.