It was cute... not my favourite story of this author but I think the storytelling was something I got to appreciate a lot. I've been reading some really shitty manga recently and having this back again, this subtly way of communicating a lot of stuff in a manga, felt way too good and I'm probably going to give this a rating that it doesn't deserve, but well. It is what it is.
Normally I'm not in favor of the argument "all sex scenes are unnecessary" because for me they are like any other storytelling device. They can be useful depending of the story even though I do think sometimes the are being used just for the sake of using them (even though they are not the only one, and even not the most overused one, but I guess people make such a fuss with it just because it makes them kinda uncomfortable). But in this case in particular, the sex activities they were having while being really young, although not unnecessary (because it's used for a reason in the story), it's way too explisit. It could have been done with the exact same effect without being this explicit, so that's my major issue with this.
It's a cute story, I loved the art and the storytelling since it was so well done in a moment in which I was starting to think that people can't do it like this anymore (I hate u shounne mangakas), but that first sex scene was a little too explicit.
Ryou Katakoi no Susume