Safety: Snorkeling is very safe, but basic Japanese and English are needed. The price is very cheap.
Experience: I fed a lot of fish, but it cost an extra 1,000 yen, which is optional but worth it. Renting equipment costs 3,000 yen, which is also optional. The instructor took over 100 photos of me, and he was very nice, letting me touch sea cucumbers and other things. If you speak Japanese or English, you should definitely go! It feels very safe, and I felt like a fish.
Location: Because of the waves, we changed to a safer beach.