A UK man has gone online to crowdsource a jeweller to create a unique item - a ring made from his own sperm.
The father of five went on to online marketplace Bark.com to ask for help with his plan, which he said he conceived after reading about similar rings made from breastmilk.
He revealed he was planning a vasectomy at the end of the month and wanted to immortalise his "manhood" before he got the snip.
He said he and his wife of more than 20 years often give each other prank gifts and he wanted to outdo himself this year.
With a budget of £1500 ($3000), he reached out online to help someone execute his vision.
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He wrote: "I know this is super weird, but I'm due to get a vasectomy at the end of November, and I wanted to do something funny with the last few living sperm I've got, kind of like a keepsake of my manhood.
"The plan is to give the ring to my wife on Christmas day, wait for her to tell me it's beautiful, let her wear it for a couple of hours, and then tell her what it's actually made of ..."
He added: "So you don't think I'm a complete nutter, my wife and I have been together for more than 20 years now, have five kids (hence the vasectomy haha!) and since day one we've been pulling pranks on each other with quirky presents – this will hopefully be the best one yet though.
"I know this type of jewellery can be quite expensive (I saw some breastmilk ones online), so I've set aside around £1500 for the ring, I'm not really looking to spend any more than that."