Can a spirit leave an object in your house?
Short answer, yes.
If so why would they do it?
As many different reasons as there are spirits who do it.
Why did you decide that it wasn’t particularly pleasant? This reaction seems to owe itself more to your pre-formed ideas than to an objective decision. Was it the colour? Or that it looked like what you think a ‘demon’ looks like? And that you think ‘demons’ are …what? Bad? Evil? Or maybe I’m way off beam here. I’d be interested in your reasons.
Short answer, yes. As many different reasons as there are spirits who do it.
Why did you decide that it wasn’t particularly pleasant? This reaction seems to owe itself more to your pre-formed ideas than to an objective decision. Was it the colour? Or that it looked like what you think a ‘demon’ looks like? And that you think ‘demons’ are …what? Bad? Evil? Or maybe I’m way off beam here. I’d be interested in your reasons.
It just looked rather menacing, with it's location it felt like it was there for a reason but not to be found, also as it spooked me a bit and I have shy'd away from paranormal things and I must admit my house feels peaceful no sounds no one walking aroun upstairs.
Maybe i had been sticking my nose into something that i shouldn't be :/
If I were investigating this, I'd start by asking the house spirit what is going on. Even if he/she/it hasn't done it personally, he, she or it will know who has.