Mathew,
It is great to acknowledge your sex-appeal to other men. ^_^
In general, I think dating colleagues especially in Tokyo is a bad idea.
Unless both can keep it utterly private it is a sure path to trouble.
Whenever a female co-worker (no matter how hot) made some advance or simply gave some indicators of interest, I say I already have plan with my GF (even if I don’t have one at the moment).
You don’t want to alienate her/him either, after all, you are working with that person and see her/him almost everyday.
Cheers
F.
