Ouch. Looking at naked pics is questionable as it is (but perhaps things like this do happen) but sister hmm I don’t have a sister but I have grown up daughter and niece and sister in law (brother’s wife).

If my husband looked at their naked pics (if hypothetically they had naked pics of them for bizarre reasons), I’d be done with him. What a betrayal!

I’d also feel for their safety, if they stay at my house would he sneak around trying to see them naked? Heck no. Your guy isn’t to be trusted