Oscar gave his fiancee a $33,000 engagement ring. A week later he found out she was cheating.

The co-founder of PedestrianTV, Oscar Martin, has reached out to Facebook hoping to sell a $33,000 engagement ring.

The ring was purchased for his former fiancée, Megan Blake-Irwin, who has since been linked to Kourtney Kardashian’s ex-husband Scott Disick.

The 1.23 carat Cartier ring is virtually new and was posted to a Facebook page dedicated to purchasing designer goods.

As the ad so bitterly reads: “Note this ring was worn for one week only.”

Soon after posting, Martin was bombarded with questions from members desperate to know what happened between him and Blake-Irwin.

One member wrote, "What happened???? 2 weeks and then the engagement was over? What silly girl was say yes to this beautiful ring and then give it up?"

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Within two minutes, the seller was back to explain what really went down and there's a very good reason that she's a *former* fiancee.

After being engaged for just one week, he discovered that she was sleeping with someone else.

That somebody else was her own ex-fiancé.

Images via Facebook.

Making it even worse.

From there, Martin became quite the man of the moment.

One member wrote, "I'll marry you Oscar" with over 54 people agreeing with her. And another said, "I had a bit of a stalk [of his social media] and he does seem quite a catch".

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Despite the many (and we actually do mean many) proposals of marriage, Martin said he was off the market - for real, this time.

"I've seen met an incredible girl and have fallen well and truly head over heals. It's quite the story...With a very happy ending. Now buy the ring someone."

So... anyone got a spare $28,000?