Male sparrow opening window wider multiple times

Hi everyone. First time posting.

I’ve been put on bed rest today. While in my bedroom I kept getting a little visitor to the window. At first I thought maybe he was checking if his reflection was another male. But his actions made me question that. He would sit on the windowsill and watch inside. He didn’t seem to fly away at any movements made inside. He would if something made a loud noise out side.
he started coming back and would bang against the window until I would talk to him.
I had my windows open just a crack and the cheeky fella started getting under the frame and wiggle and pull until the window opened a little further. He’d then sit on the open part and watch inside ( I’ve posted a photo below of him under the frame doing it)

I noticed this evening that he’d even started a little pile of food by my window. 

he’s chirping away while he’s on the windowsill. It sounds strange because I know wild birds usually don’t want attention and would fly away. But he seemed to make a racket until I’d talk to him and at least sit up and watch him.

it may sound totally bizarre, which is why I’m asking  if anyone could help me identify his behaviour.  

we have a large flock of sparrows around our house. Among other birds. We have a woodland area behind our home  so we’ve been watching sparrow fledglings taking their first flights over the past week or so. My daughter is home educated and we actually spend a lot of time observing the birds in our back for their behaviours. The sparrows are definitely the less skittish of the birds. They come in to our garden to feed even when we’re in it etc. I’ve had one taking food out of the feeder as I was hanging it back up after refilling. But today has been totally different for sure.

thanks in advance