Forget wearing your heart on your sleeve. Now you can wear it on your backside.

Forget wearing your heart on your sleeve. Now you can wear it on your backside, with “Tailly” — an attachable tail that wags when you get excited.

How does it know what you’re feeling? Tailly has heart rate sensors embedded in the belt that holds the tail. When your heart rate is high, the tail spins around like a dog ready for walkies. When you are calm, it swings slowly.

The furry accessory, which comes in white, black, brown, and gray, is the brainchild of Japanese inventor Shota Ishiwatari. He first made his mark by developing the necomimi, wearable cat ears that are said to “interpret your brainwaves” and reflect you mood by drooping, wiggling and perking up. People wanted matching tails, and that’s how the idea for Tailly was born.

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Ishiwatari’s Kickstarter page, through which he was trying to raise funds to produce a first run of Taillys, explains more about the product. In a video on the site, two friends meet up in the park and share a tail-wagging treat — a Japanese pastry. The site even suggests you put one on for a date and “express your true feelings through the wagging tail.”

Ishiwatari had planned to manufacture 3,000 Taillys in August 2013, but don’t get wagging just yet — he fell short of his fundraising goal last week days ago.

In the meantime, you can check out his Kickstarter page, and read answers to some of your burning questions about Tailly such as, If it’s a cat tail, then why does it wag when it’s happy? Ishiwatari’s somewhat garbled answer: “I am also worried that. Heart rate is dependent on the tension. It is dog which animal was wagging the tail at that time.”

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