Sister Caught Me

Back from 2023, my sister always wore tiny shorts where half of her ass was out, or some so sexy tights, i know she is my sisters but always when i saw her half booty naked, my dick start pulsating.
One time she was in bed and get up to go to the toilet, she was in t shirt and some hot red lingerie thongs, my dick saw that and started to finding way out of boxers, i ran to my room and started to jerk of my dick, it was so hard.
My sister opened the door and saw the whole thing, but she just went in smiled and said "mom is calling you", i covered my dick the first second but i know she saw it, and she went out.
The next day we were in living room and i got boner in front of her, i took the pillow and put it on my boxers to hide it, and my sister started smiling and said "why are you hiding that little dick"(just to provoke me, because it is not small, its about 19 cm), and i said "it is not small", she smiled and said " then why are you hiding it, it must be small look at your face you are getting red", i said " i covered it because you are my sister", she smiled " so what" and took the pillow so fast i couldnt react, her eyes stayed on my boner in black boxers, and she said " no way" , and grabbed it few times, i was defending, and my dick went out, until this day i stiil see her face from that day, she looked amazed, said to me" nice dick bro" and went smiling, next few weeks she was always smiling when i was walking by her in my boxers.

I still jerk off to her, every time she get me horny, by her hot styling.
I would like to talk to her about that day, because now i would show her my dick and maybe got something more, but i always think that is inapropriate, she is my sister...
I know that, but i know she enjoyed that, she is the one who wanted to see my boner, she is always smiling when see me in my boxers.
Should i talk to her, i dont want to lose my sister, but i think there is something beetwen us, i always dreamed about cumming on her ass