Just days after her brutal public humiliation at the hands of Thailand's King Maha Vajiralongkorn, the monarch's former bodyguard turned mistress has reportedly vanished.

Sineenat Wongvajirapakdi has not been seen since Monday, when she was stripped of all her noble and military titles following accusations of "disloyalty".

Sineenat was the first woman in nearly a century to receive the title of "Chao Khun Phra" (Royal Noble Consort) when the king bestowed it upon her on his 67th birthday in July, News.com.au.

Now there are fears the 34-year-old former army nurse affectionately known as "Koi" has been banished from the kingdom, doomed to live a life in exile just like King Vajiralongkorn's three ex-wives.

On Monday, Sineenat was condemned for "acting against the appointment of the queen" in a strongly-worded royal command broadcast on national television.

King Maha Vajiralongkorn sits on the thrown with his official consort Sineenat Wongvajirabhakdi at the royal palace in happier times. Photo / Thailand Royal Office via AP

Branding her "disloyal", "ungrateful" and "ambitious", the palace said she took advantage of her position by falsely claiming royal prerogatives to issue orders above her station.

It accused her of "making people misunderstand her position to gain profit and popularity for herself" in a bid to secure a role equal to that of the queen.

Hours after the brutal takedown, the palace set about erasing all trace of Sineenat from the public arena, removing 60 rare images from its website and shutting down her social media.

The extraordinary, action-packed shots showed the former concubine in swashbuckling situations such as flying a plane, taking part in military drills, parachuting and firing a gun at a shooting range.

Other pictures show Sineenat and the king — who completed a five-week military training course at The King's School in Sydney before attending the Royal Military College in Duntroon, Canberra — in matching camouflage fatigues.

An unverified Instagram account, believed to have belonged to Sineenat, was deleted within 24 hours of her sacking.

"Royal Consort Sineenat has been committed physically, mentally, intellectually, and with all her ability to fulfil the wishes of King Maha Vajiralongkorn to ease his responsibilities in improving the lives of the people," one of her last posts read, according to Reuters.

Sineenat Wongvajirapakdi has been stripped of all her titles in the palace and the military, where she was Major General the Thai Royal Air Force. Photo / Thailand Royal Office via AP

Furious at the loss of a woman who had been his bodyguard, lover and confidante all rolled into one, King Vajiralongkorn turned his attention to Sineenat's inner circle, sacking six palace officials including "a nurse at the bedroom guard service" and a veterinarian.

The monarch has three former wives, none of whom he is on good terms with.

In 1977, the then Crown Prince Vajiralongkorn married his first cousin Princess Soamsawali Kitiyakara, who bore him a daughter Princess Bajrakitiyabha, born in 1978.

Soon after, he started a live-in affair with Thai actress Yuvadhida Polpraserth with whom he had five children.

Princess Soamsawali turned a blind eye to her husband's extreme infidelity, sticking by him until 1993, when he sued for divorce in the family court.

During court proceedings, the crown prince claimed his wife was entirely to blame for the failed marriage.

Thanks to Thailand's strict lèse majesté laws, which prohibit criticism or defamation of the royal family (insults carry a 15 year jail term) Princess Soamsawali was unable to defend herself and was forced to agree to the divorce.

King Maha Vajiralongkorn and fourth wife Queen Suthida. Photo / Getty Images

His second wife, Sujarinee Vivacharawongse, discovered her marriage was over via a series of nasty posters placed on walls all over the palace by the then crown prince.

According to Reuters, who obtained a photograph of one, the posters ordered Sujarinee banished for adultery, child abuse and fraud.

After the pair divorced, she and her four sons fled to the United States, where they still live.

His third wife, former lady-in-waiting Srirasmi Suwadee, has languished in exile since her 2014 divorce.

The end of their union was particularly messy and saw three of her brothers, her parents and an uncle prosecuted for using their links to the monarchy for financial gain. They remain in jail to this day.

King Vajiralongkorn's fourth wife, his longtime consort Suthida Bajrasudhabimalalakshana, a 41-year-old former flight attendant, in May this year.

Of all the Thai monarch's great loves, the most enduring was his beloved poodle Foo Foo (also known as FuFu), whom he promoted to the rank of Air Chief Marshal in 2007.

When Air Chief Marshal Foo Foo died in 2015, he was cremated after four days of Buddhist rites and mourning.