If you've read/watch your Senryuu Shoujo, your Kono Bijutsubu ni wa Mondai ga Aru, or something adjacent (Seitokai Yakuindomo, Atsumare! Fushigi Kenkyuubu, GJ-bu, D-Frag, Hyouka... kind of, etc) then you'll know what to expect.
You get a simple premise but in this genre execution is everything, making the mundane funny will make or break these kind of series, and I'm happy to tell you that R15+ ja Dame desuka? delivers. The artstyle variation in a single page (often in a single panel) really works well than it has any right to be, it's one aspect that stood out the most to me when reading this; many comedy manga do this, but usually it's for a punchline and not something constant, this series on the other hand will have an artstyle variation in practically every single page. You'd think it'll get old real fast, but surprisingly it feels natural as if this is how the manga is supposed to be and I completely adore it. This series also introduced a mystery for some intrigue to keep in the back of your mind, I doubt it'll end up to be anything mindblowing but small things like this is very much appreciated to keep the readers engaged wanting to read more, anxiously waiting for the next chapter/volume.
The characters are very loveable. Amou is curious and inexperienced but she's not stupid, she's like Chitanda Eru if you turn her innocence and awkwardness up to 11; Fuyumine is your typical aloof guy who mostly gets pushed around by the whims of people close to him/he's interested in, otherwise he just follow his own flow uncaring about most things in general; "Kanako"-senpai is the whimsical cute upperclassman with a useless ability and have a high tendency to do the most random stuff imaginable, she's proud of her kouhai who is finally interested in another human being.
It's a tried and true classic formula, effective in cheering you up and make your day. Highly recommend.
