"Kono Subarashii Sekai ni Shukufuku wo!" (bless this wonderful world!) volume 1 by Akatsuki Natsume. No other skills are needed when the balance of luck is finely tuned.
In most other novels with the premise of being sent to game/fantasy world, the main character will enter with some better than average skills, or meet powerful allies along the way. This novel had none of that. Kazuma had basically one advantage of being very lucky, which is very much negated by Aqua's lowest level of luck. The end result is a balanced story that is easier to relate to -- there are no heroes in this series, just average imperfect characters like the rest of us.
Imperfect characters, or more like deeply flawed. The main character doesn't portray the sense of honor typical in these kinds of novels, and applies his stealing skill to get out of every kind of situation. There is an honorable crusader, but she is a serious masochist and her attacks misses even stationary targets. Then there is the archwizard whose powerful attack can wipe out hordes of zombies at once, but can only do that once per day. Finally there is the goddess, who is basically an idiot. It's amazing that this crew can complete any quests at all, and that's why this book was so fun to read. The world might be a bit different with flying cabbages and such, but the characters are very human, and they work very hard to earn their keep.
For people saw the anime series first: this volume covers mostly episodes 1 through 6, plus about 15 seconds of episode 8. The anime is very faithful to the original novel, although some of the dialogue reads better in the novel. Note that this novel is not the original original either. It was first published online before being acquired by Kadokawa, with some edits done in the transition to printed form. There are various critical reviews from fans of the web version, but since the web version is now gone, new readers will never know. I personally find this book a pleasure to read, and would recommend it to everyone who enjoyed the anime series.
Previous (2016-04-21): "Eromanga Sensei" volume 6 by Fushimi Tsukasa
Next (2016-05-09): "Kono Subarashii Sekai ni Shukufuku wo!" volume 2 by Akatsuki Natsume