I know the translators are doing their best but most of the context got taken away.

Here’s what a japanese translator said on twt:

In the upcoming panels, he says "no" and "wait" but never actually asks Shizu to "stop," and the scene continues. This isn't seen as nonconsensual or troublesome in Japanese media until clear indication that one party is upset comes in, but if that bothers you, please stop here! That's completely valid, by the way. Be safe and put your comfort above everything else!

But from what I understand from talking to JP friends, he's just shocked (or wanting to pause) and isn't actually saying he isn't okay with this . It has a different mood than ch. 20.