UK,2 S 6 D Lilac , Sg 175 S , Stamp- Error At The Overprint ?

I found it. It is a 5 centime, Ceres,1870, stamp with ink drawings on it. Possible it was made as joke by a postal clerk or one it's previous owners when he was in a artistic mode. I call this one the "clown "stamp because it has ink drawings in front of her nose. It's quite amusing.

Enough listings of a very pale lilac unused stamp can be found online. I think they all are badly faded and never printed that way. I have seen them with overprints. It could be they have faded in a climate with high humidity.
There is no 'pale lilac' or 'very pale lilac' 2/6 listed in the SG Vol 1 catalogue. With such a distinct pale 'shade' you would expect it to be listed if it is as printed.

That still does not imply it must have a cancellation removed. That's why I would be interested to see where the cancellation that has been cleaned would have been. I cannot see a trace of that cancellation. The fading is quite uniform.

I agree with NSK, the only hint that I see of a 'cleaned cancellation' is the watermark showing through. I don't like the color though, it looks very faded to me.