Haven't read the original manga adaptation before, but since so many people are constantly only talking about it and comparing this manga to it, I've decided to check and compare the same-named chapters and... my conclusion is that I like this version more. This seems like the adaptation that tried to actually portray the story a bit more seriously and since I came into this expecting it to exactly be "a bit serious",
so far, I'm much more satisfied with this version than the other one.
But still, in both versions, it seems like Shimamura is like a gender-bent typical male harem protagonist, lol.