Getting semi-back on track, when I first saw this topic, I thought of another Super NES game,
Sink Or Swim, which, as you can see by its box art, is also referred to as S.O.S. I think my only encounter with this was a brief mention in Nintendo Power, and I find it weird that I remember such odd things. From the looks of things, the S.O.S. that you brought to my attention looks way more interesting.
How did you find S.O.S., anyway? Seems obscure. I always think I have such a comprehensive knowledge of (North American-released) NES and Super NES games that I'm surprised to learn of games I've never heard of. At first I thought this was a Japan-only game like the original Clock Tower but apparently S.O.S. was indeed released in North America, according to GameFAQs...