Since Amy was the first girl added to Sonic's harem, it was only natural for Cream to be the first girl added to Tails' harem. I always see Cream as Amy's Tails. Plus, there is so much Tailream fan content. Even SEGA acknowledges it sometimes.

When writing Cream, I had one rule: she is not allowed to cuss. Even during sex. Speaking of which, pre-dating Cream, she did know what sex was, but was too naive to put two and two together about what causes arousal. During dating, she became more the same, but with some of Amy's influences.