Quick backstory: my brother in law is staying with my wife and I while he attends grad school in our city. She’s a senior in college

His girlfriend stayed the night last night and it was just the two of us today. I work from home and my wife was on site today. BIL caught an early train to school.

I had to run out to a client for what I though would be 2 or 3 hours. Turns out in only took about an hour so I was home early. As soon as I walked in the door I could her moaning from the guest bedroom. I quietly walked down the hall to the bedroom and peaked through the crack in the door to see her on her back, legs spread going ham on her pussy while watching porn. I backed up so I was sure she couldn’t see me and started stroking to her sexy moans. It didn’t take me long to erupt thinking about her young pussy.

Maybe next time she stays the night I’ll be able to snag a pair of her panties.