Spajiro is notable for its almost endlessly customizable pastas - there are some fifty different basic variations in tomato-based, cream-based and shoyu-based (Japanese-style) sauces. On top of that you can choose from twenty-five optional add-on ingredients (try the toasted garlic!) and four portion sizes.
The big selection of Japanese-style pastas is especially recommended. Showcasing ingredients like asari clams, natto and mentaiko (spicy cod roe), the pastas are true to tradition but somehow a bit more modern in feel than other Japanese pastas around town.
If you'd like to make a full meal of it, there are good Italian side dishes like arancini rice balls and garlic-sauteed spinach to supplement your noodles. Pasta bowls start at under Y1000, and drinks and side dishes are reasonably priced.