I'm not a comic creator so no drawings but I feel the question can be answered for novels as well so let me be shameless 
I actually have quite a few married couples in my main series. The most obvious are the MC's parents and he even has two sets of them: One in his actual life as a god (because why shouldn't gods get married and have kids?) and one in his trial where he's reborn as a human.
Two of the main characters have also ended up as a married couple in the first version of the series (still quite a ways off in the revision here on Tapas though but they'll get there!) and they're probably the most fun couple in the series since you see them first hearing about each other, then witness their first meeting and follow one of them very shamelessly pursuing the other one and finally getting married.
Then there are also random side characters that are married (some secretly though where almost nobody knows about it and even the readers will only find out about it in side stories or from very small clues) and even the so-called "antagonist" is married.
I think that all of them are important in so far that their relationship will influence other things. E.g. if the MC's parents weren't married and he only had one of them to take care of him, he would have turned out a completely different person and many things in the plot would have changed because his father and mother go about things very differently.
Then there are marriages that are very unhappy and will be important because of that. One of them is even standing in the way of a happy relationship and screwed up the lives of several people spanning two generations.
So I think the marriage mostly shows traits of the two people in question but influences the people around them and with that do their part for the plot.