Balmain’s Olivier Rousteing said his starting point this season was last season’s after-party. Scroll back through the months and you’ll recall Rihanna, a sheer mesh top, and a much-liked Instagram pic. “Let’s free the nipple, you know what I mean?” he said backstage. As it turns out, there were no exposed nipples here, but there was a lot of skin and no shortage of transparencies—from the plastic inset on the hem of a mini, to the plissé mousseline of swishy flares, to the sheer nylon knits that have been popular on other runways as well. But for a show that was about “pushing the boundaries of sex,” as Rousteing bluntly put it, it didn’t always read as sexy. The issue, in most cases, was the fabric. As eye-catching as allover crystals can be, they’re hard to slink in—harder still, we imagine, to sit down in. And the same goes for Rousteing’s leather. It was most convincing in small portions, like the striped bandeau worn with belted, high-waisted pants. When he balanced his instinct for embellishment with simplicity, things started to click—see the draped white tee tucked into a pencil skirt made from a Mondrian-ish grid of intersecting crystals. But in the end, this collection was at its best when Rousteing was thinking streamlined (a black bandage dress with cutouts that bisected the midriff) or sensual (Joan Smalls’ strappy, plunge-front dress and sheer pants in fiery red).