>>937365700
So when i was 15, my sister 11 at the time suddenly had a total personality shift.
She started wearing the skimpiest outfits she could, started modifying her t-shirts and making them all bare midriff and stuff like that.
My brother (13) asked me if she had started flirting with me too, since he had noticed she was flirting heavily with him and dad. Now i was totally oblivious but once he mentioned it i noticed it.

She would often come into my room in just her bra and panties on and this went on for a bit.
Then one day after i jokingly/mockingly asked her why she's wearing a bra when it has nothing to support she started coming into my room topless.
She acted like nothing changed, still coming in to annoy me and tease me.
So i jokingly said asked her to at least come in without panties on. a part of me wanted her to do it but when she did i was genuinely shocked.
She must have noticed quickly that i could not keep my eyes off her when she did that and she started sitting on my bed with her legs somewhat spread, not too much just enough to show a little.

One day i just went over sat next to her and started rubbing her pussy while kissing.
at that point it was all on rails after that.

After we first had sex i asked her if i was her first and she said no, but would not elaborate.
a few weeks later my brother buckled and fucked her.
It was shortly after that we noticed that her interactions with dad became very weird, like he didn't want to look at her but she was even more flirty.

And about 6 months after her ho phase started it abruptly ended. She still hooked up with me and my brother after that but not as often. and only for a year ish after