scary jelly fish

I've always been scared of this animal, since when a friend of mine was unlucky enough to got touched by one of them, and I can recall was quite unpleasant for real!

During my life I got touched just one time by one of them in the mediteranean sea, more specifically in Spain and it was very painful.

So when I saw this monster directly from the ocean beached on the sand, I got really scared.

What if such a size jellyfish would have got in contact with me or one of my sons?