The “uncles” come in different packages, the basic one provides a man in his 30s or 40s who will reportedly walk with the pupil to and from school while repelling bullies.

The “evidence package” offers an uncle who will film the bullies and give the findings to the school. As a bonus he will threaten to make the footage public in the event the school fails to act.

The “chaperone package” sees the uncle visit the bullies parents at work and shame them.

The unusual service in South Korea occupies a legal grey area and may be linked to the criminal underworld.

Noh Yoon-ho, a lawyer in Seoul, told The Telegraph she has witnessed an increase in legal action over bullying since she began practising in 2012.

“The media has been reporting a lot on school violence, more parents are becoming anxious,” she said.

“Previously, if you looked for these services on the internet you would never find them but now one or two are popping up, which means there must be a growing demand.”