There are few pets that we'd allow to feast on our blood. A puppy? Sure. A kitten? Lose the attitude and we'll talk.
For people who keep leeches as pets, it's a necessity. Just like you should never get a puppy for Christmas, you shouldn't get a tank full of leeches if you aren't prepared to feed them copious amounts of blood.
Yes, it turns out that keeping leeches as pets is a thing, and while with some species it is possible to feed them blood from dead animals (like Angel from Buffy), it turns out there are plenty of pet owners out there (thank you Science Alert for flagging it up) that will feed their beloved pets on their own heart juice.
While the idea may seem a bit icky, allowing leeches to suck the blood of humans has been done for over 2,500 years. In ancient medicine, leeches were used to remove blood in order to treat everything from hemorrhoids to blood loss. As the scientific method was applied, it was found to not be effective (and actively harmful, given the risk of infection) for the large part. However, it is still used today for specific purposes, for which medical leeches are grown.
"In medicine, particularly plastic and reconstructive surgery, leeches may be used to help improve blood flow in an area of tissue or a skin flap that has poor blood circulation," the National Health Service (NHS) of the UK write on their website.
"Leeches do this by removing clotted blood (congested blood) from delicate areas, such as underneath a flap of skin or on a finger or toe."
However, these people do it merely to keep the leeches alive, some feeding them individually, others choosing to invite everybody to the same party.
While it looks painful, owners of leeches insist that it's worth it because of how great they are as pets, and they are weirdly fascinating. Hell, even, upon occasion, quite cute.
"Spent my Saturday feeding H. verbana," one entomology student wrote on Twitter. "He only fed for about 20 minutes but I bled for about 18 hours! Leeches are fascinating but definitely not a pet for the faint hearted!"
What's more, depending on the species of leech you may not have to feed them for six months at a time.
"The bite of a leech can be almost painless, lasting just twenty minutes or so until it's had its fill and releases its suckers, a process I remind you needs repeating only once or twice a year," leech and horror blog Bogleech wrote. "There's even a lot of people who've found that leeches help to relieve their pain or stress."
Might we suggest a squeezy ball, rather than... this.
The practice isn't without dangers.
"There is a small risk of infection from the leech," the NHS advises on their website, explaining that doctors will usually administer antibiotics during any leech therapy, as "they contain bacteria in their gut which helps them digest blood".
They also warn that blood may ooze from the wound for several hours after the leech has been removed, as they produce a powerful anticoagulant to stop their host (in this case, their loving owner) from clotting, making it easier to continue their feast.
So be careful, or maybe try a puppy.
[H/T: Science Alert]