exiting then re-entering the country

Here's my question--my bf is stationed in okinawa in the airforce and I'm a student doing an online course from back in the US. I want to go and live with him, without getting married. Has anyone had experience with exiting and then trying to re-enter the country more than once?? I grew up in Thailand and we used to do visa trips every 3 months and just leave for a few days and then come back in for an extra 90 days---how does japan work with this??? are they really strict??? I don't plan on working in the country!!!

thanks folks :-)

If you stay the full 90 days, exit and then come back in again very soon, you will most likely be allowed in again but only that time, and expect to be questioned.

I believe there is a limit of 180 days in Japan with a tourist permit in any one year, so you won't be able to do it indefinitely. Japan is far stricter than Thailand on this.