Marriage Quest finally on the horizon! Yay!

[Gnova]

If anything, you can do it for the perks that will no doubt come with being married and marriage housing and stuff along those lines. Just pick someone in your FC that has the same idea about it and shack up with them.

That sounds just like real marriage.
As a male you do it for the "perks" (I'll let you decide what the perks are) but regret your decision when you realize all the perks were front loaded to sell you on the concept, your partner wants you to change FCs because they don't like your guild mates, and then they use a pandora potion soon after the ceremony changing the character design enough that the loss of "perks" doesn't really bother you.