"May I borrow that?"

I have always been the person that people loves to borrow things from. Pen,pencil,ruler,eraser whatever else they needed,I was their supplier. I don't why I couldn't reply people with a "no".
I guess,I was too nice and too afraid to say so. So people had the habit of borrowing things from me. It was really bad,I lost quite a no. of things because some people are unappreciative and never return the stuffs back. I soon realised that people were taking advantage of me.

Then there was this one time during ART class. This boy came to me to my table and just took away my sharpener. He placed it back on the table after he was done using it. He never asked or spoke anything to me. I held my sharpener firmly in my hands.

"He's going to come back for it" I thought.

And my guess was right. He did.

This time,seeing that the sharpener was in my hands,he asked if he could borrow it.
I looked at him,I don't know what had came over me,but it was probably out of fury and frustration and I said,

"Shouldn't you at least say "thank you"? You've never said that to me before after all the things that I gave and lended you."

For a minute there,I swore he looked surprised, because I never had the courage to say things like that.

But after a minute,he simply replied,

"Why would I want/should say "thank you" to YOU?"

My heart sank just a little bit after hearing those words from him.
And the sharpener? I still lended it to him despite what he said.
I think I need to stop being too nice.