South of the Equator and East of the Prime Meridian, could be the Indian ocean.
"degree's south and degree's east" are too vague and can cover several oceans depending on how far you define the question.
South Pacific Ocean
W degrees south and w degrees east would be located in the Southern Hemisphere and the Eastern Hemisphere.
The body of water located at 15 degrees south latitude and 70 degrees west longitude is the South Atlantic Ocean.
There can be no such body of water, because no place on Earth can have a latitude coordinate greater than 90 degrees. The north pole is at 90 degrees north latitude, and the south pole is at 90 degrees south latitude. Those points are the farthest north and south you can go, respectively.
15 S 75 E is the Indian Ocean.
Those co-ordinates would place you in the Atlantic ocean - to the west of Africa.
That point is in the Gulf of Guinea, about 380 miles south of Accra, Ghana.
The South Pacific Ocean.
That is the Pacific Ocean.
The body of water located at latitude 0 degrees N and longitude 160 degrees W is the Pacific Ocean.
The body of water located at 20 degrees north and 90 degrees west is the Gulf of Mexico.
Lake Superior