Innocence in pop exists to be tweaked, twisted, or thank you, Miley Cyrus twerked. Katy Perry treats it like a neato vintage find. Lady Gaga channels it into a wide-eyed fascination with everything meta. Ariana Grande whose kicky debut, Yours Truly, is essentially a love letter to the concept of ''going steady'' feels, by comparison, immaculately conceived. (If you know about it, it's probably because it already delivered a top 10 hit, ''The Way,'' seemingly out of nowhere.)
Grande, a Nickelodeon star whose latest show, Sam & Cat, debuted in June, can't make an art project out of her innocence just yet. Or press the blinking red SEX button, either: She's 20, but looks younger. (Album artwork that showed her wearing lingerie on a bed of roses was deep-sixed after she teased it online.) So what's left? One of the most purely enjoyable albums of the year, powered by her lithe, Broadway-honed voice and a canny exploitation of her most ''adult'' indulgence: nostalgia. Yours honors '90s-style R&B as surely as it does '50s-style dating. Grande's not only a ringer for Mariah Carey in octave-stacking mode, she's also got boppy tracks (''Baby I,'' ''Right There,'' ''Lovin' It'') to rival early-Mimi classics (think ''Someday'').
Grande and her producers freshen the sound with a little doo-wop, an EDM twist in ''Better Left Unsaid,'' and with-it rappers Mac Miller and Big Sean. The latter slyly acknowledges Grande's chaste image in ''Right There,'' crediting the ''missionary'' position for his player status. Ariana's innocence isn't sacred, of course, but the fact that she wears it as lightly as she does may be a small miracle. A-