Kai, a Japanese restaurant in Greenbelt has quite a few vegan options. I tried the cauliflower tempura with teriyaki sauce- my favorite vegetable and favorite sauce in one dish- and I loved it!
This section of their menu is vegetarian and can be made completely vegan. Other vegan options can also be found in other parts of their menu.
Kai is located at G/F Greenbelt 5 in Makati.