I've just gone into Ables and there was a mask which was called -

DimentioMSK HDLC

I thought HDLC was hacked downloadable content - how did it get on my game?

I don't have any visitors or visit anyone else!

Kat x

Kat, yes, it's hacked downloadable content.  Have you NEVER had a visitor?  Not even a delivery from a giveaway?  The person doesn't have to go into your Ables for you to get it.  Just someone traveling to your town will do it.  And it doesn't have to be recent either.  From what I understand, Dimentio acts like any other Able accessory.  It comes up completely random, so there really no way of telling who you got it from, or how long you've had it.

Yes, I've had deliveries of flowers, so that must be where it came from.

How do I get rid of it, will it stay in my Ables forever?

Well, from what I understand, it will come and go like everything else at Ables.  And if you've had deliveries of flowers, I would agree that's where it came from.  I would imagine that almost all deliverers have it.  It's spreading so rapidly, and you can get it without even knowing it.  Boy, is sounds like some horrible illness when I say it like that doesn't it   But the good news is, no one has shown any ill effects of having it in their town that I've heard of.  It's just the general idea of having a hacked item in your town that bothers so many people.