This small review is spoiler-free. "Kumo desu ga, Nani ka?" was the first manga that kept me interested enough to read LN and I tell you, it was very much worth it.
Story: So far manga covered the less plot-focused part of LN. The story is very straightforward with the protagonist "grinding levels" to get out of a great dungeon. The best (for me) part about it is that story doesn't try to forcefully shove new characters or major plot twists in there just to keep you interested: it is entertaining enough by itself just to see the little spidey getting stronger in a most logical and realistic (given the setting) way possible while still being lighthearted and cracking jokes here and there.
Having read the LN I should tell that the series takes a complete 180° turn and becomes completely focused on the plot pretty soon.
Art: the art is of high quality. It's not overly detailed or realistic. Instead it is on the cartoonish side to keep the light tone of the story. The main character - spider - is cute and the artist managed to make it very expressive.
Characters: right now in manga Kumoko, the protagonist is the only sentient character and her action are very believable and she gets plenty of chracter develompment later on.
This manga also inspired me enough to write my fist review here so I can't wait to see the anime based on it that was recently anounced!
