I think that an interesting approach would be to give characteristics of both characters as a couple. The most elemental trait they share when they are a couple is that they seek to be discrete. They understand what is at stake in their relationship, in that their presence together is forbidden by Big Brother. The very idea that they would share emotions and moments of sensuality that cannot be controlled or appropriated by Big Brother makes their status as a couple dangerous, requiring the utmost in discretion. I think that another trait they share is that they both enjoy sexual activity. Their penchant for sex is heightened by both of their work and resentment of the government, where sex is only meant for procreation. I think that the last descriptor of them would be that their bonds are ruptured at the very end. Both of them end up betraying the other. The meeting in the park reflects the nature of the ruptured relationship between them. Something that held so much in emotion, intensity, and commitment was undermined by Big Brother, resulting in two people who can only say in the most plain of voices how they betrayed the other.