Japanese girlfriend wants to try new things

We are a Japanese Europen couple living in Tokyo and we just started to broaden our horizons.
We want to explore the hot girlfriend lifestyle and are looking for similar minded people in Japan. Also for meeting, talking and having a good time together.
I am also looking for other guys who have tried this way before with their wive of girlfriend and talk about their experiences.

She is in her mid 20s and I am in my 30s. I can speak Japanese and she can speak a bit of English.