Although there is little online information about the Champions Clerum tournament, it appears to be an existing religious only indoor soccer tournament that has had several editions in the past. Anyway, there is evidence that the Clericus Cup, a similar tournament held in Italy is still being played each year, as seen in their website.
Juan Manuel Montilla "El Langui" is not only an awarded actor (best new actor in Spain's Goya Awards), but originally and mainly a well-known hip-hop singer who has also written two books about his vital experiences as a handicapped person.
The sweets manufactured at the monastery, the "perrunillas", widely mentioned in the film, are an actual convent and monastery recipe from various regions of Spain, a sort of tea cookie.