To cheeri someone's o is to please their vagina or anus. Cheeri my o is an instruction to do this by means of manual stimulation.
Cheerios are also a sugar-coated breakfast cereal.
Cheeri my o is a verbal phrase, therefore: keep cheeri-ing my o, yesterday peter cheeried my o etc are all acceptable.

I've been corning your flake all morning, it's time for you to cheeri my o.

He cheeried my o for hours so in return i sucked his crunchy nuts
by charrc April 24, 2006
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