The bond system in Revue Starlight ReLive is a way to strengthen your stage girls and unlock materials and new stories. The Bond level is mainly increased through giving your stage girls gifts and playing the main story.
The Bond System and upgrades can be found in the “Stage Girls” menu option.
Gifts are by far the easiest and most efficient way to increase your Stage Girls' bond level. Each Stage Girl loves a different type of gift, but Flower Bouquets are universally loved by all Stage Girls. It is recommended to maximize bond point gain by giving Stage Girls their preferred Gifts.
Elastic Hair Bands
Bond EXP via Battle
Similar to EXP, bond points can also be earned through the Main Story. The amount of bond points earned in a level varies; however, it does tend to increase as the levels become more difficult.