This set of snap-together boxes can be assembled as a heart or any number of infinite combinations and shapes. They are designed to print in “spiralized mode” to save on time and materials and to look great with multicolor filament.
See here for video: https://youtu.be/rQ85kKHYEmY
See here for stable download: https://social.thangs.com/m/638947
To make the Valentine’s Heart Box you will need to print four “Corner Piece Round Edge” and one each of “Corner Piece Straight Edge,” “Inside Piece,” “Side Piece 1,” and “Side Piece 2.”