A person whose entire life revolves around one thing and who is
perfectly happy remaining ignorant of
real life and the
outside world.
Like how a fish is perfectly happy inside of their bowl, not even caring that there is an entire ocean out there.
Jeremy is such a fish. All he does is go to
the gym,
talk about the gym, eat at the gym, and think about the gym. Does he do
anything else besides the gym? No, because he's a fish.