@Stonecoool no, can't do. For other, its okay. But for the childlike Shizuka-chan (the mute book worm) and "child mode" meth senpai thats inapropriate.
For this manga (editor & publisher screening) and for society (you know, lately lolicon case in Japan get so many media attention in a bad way). Adult-like romance scene with child subject is considered taboo. In doujin/comiket, because it has minimal distribution & attention, it is okay. But in nationwide distributed & published manga, as popular & mainstream as this, thats just asking for an axe & social media bashing/cancel culture.
You bet your ass, this author wont risk that. Even drawing off scene child like character pissing need an apology to the chief editor beforehand to avoid trouble, and you want the author to draw THE MC FRENCH KISSING A CHILD!?