Ad blocker interference detected!
Wikia is a free-to-use site that makes money from advertising. We have a modified experience for viewers using ad blockers
Wikia is not accessible if you’ve made further modifications. Remove the custom ad blocker rule(s) and the page will load as expected.
Sea urchins were marine-dwelling organisms native to and common on Earth.
The Eleventh Doctor compared the House entity from the bubble universe to a sea urchin, in that it had a tough outer shell protecting a soft interior. (TV: The Doctor's Wife)