(noun) To be cute, adorable, or endearing. The most common usage.
(verb) To pet an animal by softly grasping them by either side of the torso/head and ruffling their fur or otherwise petting them evenly on both sides. A bit firmer than a normal pet but 'tis the nature of the scrungle.
"Just a little fella... a scrungle if I've ever seen one"
"Don't forget to scrungle your cat every night"