My step-daughter is teasing me

I feel a little bit guilty about this but I’m confused about my step-daughter’s behavior, since I married her mother we’ve always been very close, sadly my wife passed about 4 years ago, I took responsibility of her daughter and we’ve lived alone for the past years, during the fallout from that episode we grew closer than ever, but lately she’s been behaving differently.

She has always dressed extremely casual around the house but in the past few months it has changed, one morning I noticed she was wearing one of my white undershirts I wear under my button up shirts to work every day, it was surprising, what she was wearing was revealing but not too revealing, the shirt is white, thin but not overly so, and goes barely covering her buttocks which gave me a glimpse of her panties. I was surprised to see her wearing it but decided it wasn’t a big deal. It’s her house and maybe she was comfortable wearing that.

But it kept happening more and more often, I didn’t say anything because I didn’t want to make her feel uncomfortable or make things awkward also didn’t want to put myself in the position where I was telling her what she could and couldn’t wear in her own house.

She’s a stunningly beautiful skinny petite girl and I’m uncapable to not look at it so I spoke to her on this subject, the conversation would end up like this:

Her: Why is inappropriate?
Me: Because the way you dress is too revealing
Her: Why should that matter? Nobody else is around, it’s just you and me.

So, I just let it continue, one morning I was having breakfast and just couldn’t resist anymore and took the bait and grabbed her butt with my hand when she was standing next to me while we talk and for my surprise she acted normally, I was expecting her to tell me to get my hand off her or something like that. After that incident we were sitting next to each other at McDonald’s, she’s into that goth/anime style and loves pink so she was wearing a short school styled skirt and she was really close to me then I started to gently touch her thighs and again she acted like nothing was happening. I’m not sure if she likes that but sometimes I randomly start to grope her while we’re sitting on the couch or something like that, she still doesn’t give any reaction. Should I just stop doing that or talk to her about it?

Source: reddit.com/r/Erotica/comments/q7xfm1/my_stepdaughter_is_teasing_me