Shantae and the Pirate's Curse is the only game in the series I've played, but I was kind of weirded out by the sheer quantity of boobs in it. Now, I expected lots of fanservice, since I played Mighty Switch Force before, and the heroine is basically just wearing a bra, but this game took it to a ridiculous level. When even scary blob monsters have gigantic tits and every other NPC has an outfit that's three sizes too small, it kinda stops being sexy and just becomes weird, especially in a game that's also trying to be cartoony and nostalgic. It just doesn't work.
Don't worry, the original game on GBC was like that too.
Was gonna say, this series has always been big on fanservice, naughty humor and general silliness. But then they said they'd never played the other games, so it makes sense they wouldn't get it.