This must have flown in through the window - very restless - never stopped moving and occasionally spread it's wings.
No interactions present.
I suppose I should've killed it - probably it's now chomping away at our furnishings.
My favourite Lichen Site
MARINE, MARITIME AND OCEANIC LICHENS
'What is not shared is lost'
Lat/Lng: 51.5, -0.1
OS grid ref: TQ3780