It’s widely known in Japan that idol singers are often contractually prohibited from engaging in romantic relationships.

That’s why in addition to legal pledges not to date, the Japanese entertainment industry has a number of sneaky tactics up its sleeve to prevent its idols from falling in love or going on a single date.

A handful of entertainment industry executives, under the condition of anonymity, recently shared some of their methods, which involve psychological and time-management tricks as complicated as some idols’ stage routines.

One common practice is to keep the idols themselves in the dark about their own work schedules, sometime waiting until the end of the day to announce tomorrow’s timetable.

Being an idol isn’t like working a nine-to-five shift at the office.

On any given day, you could be recording songs, practicing choreography, appearing on TV variety programs, or meeting fans face-to-face at handshake events and other local promotions. This method is so effective that one talent manager says he can tell when an idol has secretly found a boyfriend, because she’ll suddenly start wanting to know the details of her work schedule farther in advance.

All of those involve varying amounts of time and being in different locations, and it’s incredibly difficult to plan a romantic rendezvous if you don’t know when you’ll finish work or even where you’ll be when you do. But in many cases, it’s not like that would make much of a difference, because another method to keep idols from dating is to pack their schedule so tight that they don’t have any unsupervised free time.

As mentioned above, idols have a huge variety of responsibilities, and talent managers ideally want them to be so busy with those that when their workday is done, the singers are too worn out to do anything other than head straight home and go right to sleep (alone, naturally).

▼ The exciting after-hours lifestyle of an idol However, there’s a complication that managers have to bear in mind regarding this practice.

Idols’ owe their success as much to their looks as their voices, and by running their performers ragged, they also run the risk of ending up with a group of haggard-looking, exhausted vocalists.