WTF Is This Creature? Please Help Me Identify It!

So, as you might know from my yesterday's post I spend this weekend in my village with @ruth-girl. We were to the beach and I was having a take-away coffee enjoying the sun and left her do her favorite thing, which is take photos of random stuff with her camera. At some point, near the shore line she spotted these jelly-like red things attached to some sea rocks.

I had no idea what they are so I followed my prime instinct and poked them with a stick. I got no reaction out of them, although I was hoping they would start squirting water or something :D

Can any of you help me identify what this creature is? I am really curious to know the species or at least the genus or family!

To help you out here's the information I can provide from my experience:

• Primarily red
• Jelly like texture
• Firmly attached to the rock. A slightly more than gentle push wasn't enough to move them from their place. I didn't want to harm them so I didn't put any serious force :)
• Relative small in diameter, about the size of a human palm.
• Spotted at the beach of Agia Marina
• They were on the underside of rocks (I had to turn that rock upside down to take the video)
• The rocks were exactly on the shore line and at that point of day were out of the water due to the tide. This suggests that these creatures can survive many hours out of the water

And that's all I can think. Feel free to ask any questions you might have, I'll try to answer them if I can!

Please leave a comment, or preferably make a post with your thoughts. I would love to read it!