I wonder if any sort of manipulation would be needed in his case, regardless of the request. [Well. Aside from being allowed to address him correctly by title.
That's a "no, I only needed to ask politely. Didn't even have to try".]
As for bringing objects to life... admittedly I'm no expert on this matter, [demons aren't much in the life-bringing business, after all] but I would assume it would revert to inanimate should the spell cease to function.
[It's doubtful it's really alive in the real sense of word, he means. Sebastian doesn't seem creeped out by the broom. In fact, when he turns to it it's with the exact same expression and tone he uses when one of the servants back home wants his help (and hasn't yet annoyed him that day):]