I’m not sure what big secret everybody i talking about? Can someone explain?

That the uke is not really a professional sex therapist. He put that ad for fun.

But did he say in the ad that he was a professional therapist?? I don’t remember seeing that.. Only that he was gonna give private lessons, which he does?

The secret is that he was told to do that by his friends as a joke or something but he actually went through with it and Is accepting money for something he is not trained to do. That’s why his friends always jokingly say that he is terrible or something

I don’t think he’s accepted any money it’s for free

It's not for free, Ahn just hasn't asked for payment yet. He has also said that it won't be expensive.