Timothy,
A content plugin which also runs on K2 items is the best solution in my opinion.
You can do a str_replace or a regex to wrap the text in the necessary markup in a tag like:
{tooltip}Example tooltip{/tooltip}.
Once you do this you can pretty much create modals, tooltips, accordions etc..
I am confident that there might be some plugin at the JED which have this functionality.
JoomlaWorks Support Team
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