I only started watching Fairy Tail recently cause it did look interesting. It had a good balance of action, comedy, drama and other thing very well wrapped up together.
Seeing the episode when he did the "Nin nin" just made me laugh without thought. I knew before then though this anime was quite special.
A very well executed cosplay and doing that pose from the anime was completely understandable. It just makes me smile everytime I see natsu do that.