Just a suggest, hoping there is a couple or a marriage.
Feature for it:
*Allowing partners to quick attack those who attack their partners who is offline.
*Allowing partners to share their special weapon like barbarian king and archer queen.
*Having a ring as a sign of marriage that can be upgraded too like a league that can earn hearts that both partners can earned loots.
*Partners can have a special weapon as a sign of a marriage.

