Khalid and Egan (not their real names) are undergraduate students at the American University in Cairo who are “deeply in love” in every sense of the fairy-tale phrase. They are desperate to marry but cannot afford it. So they turn to a solution that is popularly referred to in Egypt as “underground tube marriages”.

These secret unions, also called urfi marriages, have exploded in colleges throughout Egypt. Despite officially being banned, they have an established Facebook presence and are spawning new entrepreneurs. Weddings and dowry payments typically cost thousands of dollars in Egypt and even if a marriage is concluded to the satisfaction of the bride and groom’s families, city apartments are way beyond the means of many newlyweds.

To make matters worse, in predominantly Islamic Egypt, sex before marriage is fiercely discouraged and engaging in premarital sex can have dire social consequences. Many families in Egypt are ready to disown their children if they live as partners without official marriage. It is this pressure and the urge to engage in premarital sex that drive many students into urfi marriages.

What is required for the secret unions to take effect is simply consent between boy and girl. Usually two witnesses, often friends, sign the secret marriage agreement. After this, the consenting boy and girl are legally married. This union is halfway between the official Egyptian legal system recognition and traditional family understanding of marriage. That’s why the couples who partake in these ceremonies consider themselves “married”.

In some colleges the urfi marriages take place in abandoned lecture theatres or in secluded accommodation hostels. These are as cordial as conventional receptions. If the urfi marriage was conducted in, say, an abandoned science lab, a feast of drink and food will follow at the same venue after the conclusion of the vows. Noisy conversation and jive music in any college dormitory on a weekend is a sure sign of the celebration of an urfi union, said one elated new bride, proudly showing me an ivory-coated ring that she deftly hides from her family and outsiders.

The need for secrecy does not just apply to the couple. The witnesses, though they may welcome an invitation to officiate, also want to be secret — it is a social embarrassment to be labelled a conveyer of secret marriages.

But a girl who engages in secret marriage faces the possibility of never marrying formally if the outside world manages to unlock her secret past. If an urfi marriage does not work out, and a prospective suitor hears about her past, he could spurn her.

Urfi marriages are more about chemistry than money, even if they are not always about falling in love forever. As Egan admitted: “I could not wait for us to finish our four-year degrees and then marry. Even if that was the case, he could never afford the $7 000 and the Toyota Prius that my family demanded in order to give their consent.”

The proliferation of underground marriages has turned some enterprising students into semi-successful businessmen. Some students advertise their services on university notice boards and others offer “marriage witnesses” services on Facebook and other social networking sites.

One third-year physiology student, who spoke to me on condition of anonymity, said: “I usually charge fellow students $50 if they want me to be a secret marriage witness. I’m never short of customers — every two weeks on average — and I’m paid more thereafter to make sure I lock my mouth once outside the ‘underground’.”

It is not all merry sailing for the lovers. There is no legal status awarded to these marriages if the relationship turns sour.

The courts do not place any paternity burden on the man if these marriages end in divorce and the belligerent parties emerge from the underground to take their custody battles into the legal courts above. But Egan, who was well through her first urfi marriage, summed it up: “Urfi marriage gives me a feel-good feeling and erases my guilt whenever I want to indulge in pre-marital sex.”

Hadid Beduwi is a Chadian journalist married to a New Zealand diplomat in Alexandria, Egypt. This post was first published in the M&G newspaper.