That's also an idea. The cliques, led by these couples, are so tight and bound from being with anyone other than their own group. Eventually, some thing has to give right?

Or we could go more [@Agamous Devout]'s way and have the romance be the peace between them. The leader of the groups, the student president, in an effort to bring peace develops "arranged relationships" between them. Which could lead to some interesting interactions and drama.