An aerosol-generating system includes an aerosol-generating device and at least two consumables. Each consumable includes an aerosol-forming substrate. The aerosol-generating device further includes a device housing comprising at least two receiving chambers, wherein each consumable is accommodated in a separate receiving chamber of the at least two receiving chambers. The aerosol-generating device further includes at least two mouthpieces, wherein each mouthpiece of the at least two mouthpieces is aligned with a separate consumable of the at least two consumables and wherein the aerosol-generating device is configured to isolate airflows through separate, respective mouthpieces of the at least two mouthpieces.