Howard Ashman has an infamous note for the company, and it's still printed in the libretto that MTI licenses:
"Author's Note: Little Shop of Horrors satirizes many things: science fiction, "B" movies, musical comedy itself, and even the Faust legend. There will, therefore, be a temptation to play it for camp and low comedy. This is a great and potentially fatal mistake. The script keeps its tongue firmly in cheek, so the actors should not. Instead, they should play with simplicity, honesty, and sweetness-- even when events are at their most outlandish. The show's individual "style" will evolve naturally from the words themselves and an approach to acting and singing them that is almost child-like in its sincerity and intensity. By way of example, AUDREY poses like Fay Wray from time to time. But she does this because she's in genuine fear and happens to see the world as her private "B" movie--not because she's "commenting" to the audience on the stillness of her situation. Having directed the original New York production of LITTLE SHOP myself, and subsequently having seen it in many versions and even many languages, I can vouch for the fact that when LITTLE SHOP is at its most honest, it is also at its funniest and most enjoyable. -- Howard Ashman"