In the song 'My humps' The entire phrase after "she said" is the girl talking. This is important to note given that Will I Am is black 'your milk' refers to him and he is not the 'cocoa puffs'The girl he met was promiscuous and down for what ever. She is asking for his milk (semenal fluid, sperm, jizz) to be mixed with her cocoa puffs. Remember the old rhyme milk milk lemonade around the corner fugde is made. She is suggesting anal sex.
by Mikelyte August 7, 2017