similar to the term kitkat, when four fingers are inserted in the anus and removed covered in faeces resembling a four finger kitkat. the difference is however that instead the whole fist is inserted and removed resembling something like a kitkat chunky. this act usually takes place with the person or persons shouting 'CHUNKY' whilst inserting their fist.
ellen: oh do we have to? my arse is still sore from last time.
ellen: oh go on then, be quick...
matt: i do love a good kitkat chunky !!