Cream represents Prince's hits. They're sweet and easy to digest, in contrast to his 'coffee', the songs which are harder to take at first, but more rewarding for those who give them a good listen. That's what 'What's my name?' is on about. We never would have had a chance to hear his best stuff (coffee) if he had never served us his sweet chart-toppers (cream).

Cream and TMBGITW were produced by Prince to be hits, and in Cream Prince takes it one step further, by singing about the song's intention within the song itself, and, to most dumb-arses, passing it off as sexual innuendo. 'Cream! wow, that's so rude!'

You just need to read the lyrics:

"
It's time for u to go to the wire [get it on the radio]
U got the horn so why don't u blow it [music]
Cream [his hits material]
Get on top [number one]
Sh-boogie bop
"


So, as I take it, sh-boogie bop is just an inane kind of pop lyric, completing the mockery of Prince getting a hit while he's telling everybody about it.