There is no definition for this word, but if you say it to someone and they think you're talking about something inappropriate then you know they have a dirty mind.
"Squiggly-Sqoo!"
"What's a squiggly-sqoo?"
"I love my squiggly-sqoo!"
"You love your penis? Um..."
"No. It doesn't mean anything, you have a dirty mind"
"I love squiggly-sqoo!"
"Are you gay?"
"LOL No. You're dirty-minded."
"I love squiggly-sqoo!"
"Uh. Okay."