A bag-in-box assembly includes a box and a flexible container filled with a flowable material. The flexible container includes a front panel, a rear panel, and gusseted side panels adjoining the front panel and the rear panel along peripheral seals. Each peripheral seal having an arcuate body seal inner edge (ABSIE) and a tapered seal inner edge extending from each end of a body seal. The ABSIE has a radius of curvature from 1.0 mm to 300.0 mm. The bag-in-box assembly includes a top perimeter, a center perimeter, and a bottom perimeter as well as an aggregate contact length (ACL) at each perimeter. A top ACL is from 50% to 90% of the top perimeter, a center ACL is from 5% to 50% of the center perimeter, and a bottom ACL is from 50% to 90% of the bottom perimeter.