Once I've made gyoza dumplings for my parents in-law which they hated, I guess it was way too strong in flavor for them. It is kind of hard to introduce Japanese food to someone who is unfamiliar with it.
How about grilled skewered chicken with teriyaki sauce -yakitori and fine Japanese noodle -somen with dipping sauce. Those are super easy to make, not so weird, good summer food and visually appealing.