With the rise of digital fashion, reusing high-quality garment assets to assemble new outfits has become increasingly important for improving design efficiency and reducing production costs. However, combining multiple garments often introduces complex inter-garment intersections that are difficult to resolve. In this paper, we propose a novel framework that introduces a midsurface representation to simplify multilayered garments for intersection-free outfit assembly. Each garment is approximated by a watertight tetrahedral enclosure, enabling efficient resolution of inter-garment collisions on the midsurface level. To assemble an outfit, our method progressively untangles pairs of single-layer midsurfaces and incrementally constructs a merged midsurface. To recover the intersection-free full geometry from these deformed midsurfaces and enable instantaneous transfer across different poses, we uses embedded anchors to drive inversion-free deformation of enclosing tetrahedral cages. Through various examples, we demonstrate that our method provides a scalable and automated solution for virtual outfit coordination, enabling the direct reuse of garment assets in high-fidelity, collision-free digital fashion workflows.