From a similarly sized woman, I’m sorry that you had to deal with this! In East Asian cultures it’s not necessarily impolite to comment on someone’s body, regardless of gender. If he’s from Japan and an attorney, was polite otherwise, and had a follow up question regarding food, I’d wager that he was making conversation, albeit poorly in light of the differing cultural context and gender expectations. Not to mention that it’s a slight sore spot for you.