I get the rationale for wanting "enthusiastic consent". This manga does touch on some of the reasons why that's especially difficult for young people. Recall the way she turns him down when he's too upfront about it. She says, "Do it more naturally!" That's actually kind of how I remember it. Mutual seduction is mostly non-verbal. It's fun when you both let your ambivalence about the situation be swept away by your feelings. Stopping for consent for every change could easily spoil the mood. (Also having some sort of intimacy ranking with implied consent for anything less intimate than whatever you're doing is just kind of . . . ) The important thing is to pay close attention to your partner's feelings and back off if they don't want whatever it is. Because some people are incapable of doing that and just run rough-shod with friends, strangers or acquaintances, everyone should change how they behave in bed? all the time? I don't know.
Kind glad I'm in a long-term committed relationship, and that I'm getting too old to stray.