CREATE TABLE table_38545 ("Res." TEXT, "Record" TEXT, "Opponent" TEXT, "Method" TEXT, "Event" TEXT, "Round" TEXT, "Time" TEXT, "Location" TEXT)

Which event was in Tokyo, Japan and had an opponent of rumina sato?
SELECT "Event" FROM table_38545 WHERE "Location" = 'tokyo, japan' AND "Opponent" = 'rumina sato'
SELECT "Event" FROM "table_38545" WHERE "Location" = 'tokyo, japan' AND "Opponent" = 'rumina sato'