They say the cost of keeping a pet can bleed you dry.

But one man's devotion to his giant leech means he feeds it his own blood when it feels peckish.

A stomach-churning video of the bloodsucking parasite drinking from the man's forearm has been spared online.

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The huge bloodsucking leech enjoying a tasty treat from its owner's arm as it sits on a white counter

Red prick marks can been seen on the man's arms, although it's not clear if these were done by the leech

Not for the squeamish, it shows the bloated leech - which is as long as the unidentified man's arm - sucking from a counter as the man calmly films it in the dark, using a spotlight.

It is not known where the leech-lover and his adoring pet live, but it is thought the film was shot in Japan.

Leeches grow bigger with the amount of blood they consume, with some able to grow as long as 16 inches.

In October last year the MailOnline reported how backpacker Daniela Liverani discovered a three-inch-long leech had been living in her nose for a month, causing persistent nosebleeds.

Daniela said she had 'no idea' how the leech came to be in her nose, but thinks it made its home while she was travelling around south-east Asia.

Leeches have been used in medicine for thousands of years as part of a practice known as 'bloodletting'

While leeches aren't commonly kept as pets, they have been used in medicine since for 2,500 years, first being used in ancient Egypt.