what is this?

Fatsia?

yes I would say Fatsia, I have one very similar but I think the leaves on yours are darker

It's a Fatsia, yes. Whether the Japonica or not, I wouldn't like to say. It looks like it, but then they're usually a little lighter and glossier than that.

I keep it in my bedroom- it is not the lightest of the rooms in the house- maybe that's why it is darker- however it loves the place it is in- it didn't look very well anywhere else, until I put it there.

i'd leave well alone then, it looks very healthy