Atlus and Vanillaware revealed that there will be relationship elements with Unicorn Overlord characters in a Rapport system. This will also involve the ability for Alain to exchange a Ring of the Maiden to take part in a Rite of Covenant with one other character.
When going through Unicorn Overlord, people can build a Rapport with characters to improve relationships by eating together, fighting together, and giving gifts. Some examples of things you can give to a character guarding a town are Cut Flowers, Dice, a Replica Sword, Scented Soap, or Secular Texts. While gifts involve a single person, meals can involve a group. The screenshot showing a dinner with allies noted that something like Bacon and Soft-Boiled Egg Galettes is a meal for three and increases Rapport by 70 for 630G. Meanwhile, the Pasta al Pomodoro with Eggplant feeds four and boosts Rapport by 90 for 1080G.
Some of the Rapport bonuses were brought up as well. Stats for characters in a unit will go up if they all share relationships. Rapport Conversations come up between some people who have gotten to know each other well enough. Also, the Rite of the Covenant can happen between Alain and an ally when their relationship is maxed out, with the initial screenshot showing Chloe, Clive, Hodrick, Lex, Melisandre, Scarlett, Travis, and Yahna in the list of possible people shown in the Atlus screenshot.
Here are the Unicorn Overlord Rapport relationship screenshots showing characters interacting. The batch also features a number of new examples of Vanillaware food.
