Approach his sister, who seemed to be acting strange

Mike was hardly subtle when he just barges into Judy's room, prompting her to try to smack him away with no visible effect. She had small hands and Mike now had a big muscular body.

"Hey, don't come in here-! I'm warning you! Don't come in, asshole!" She grumbled and snarled at him, sounding a lot like puppy tantrums from Mike's perspective.

As soon as he was in, the door closed in on itself. It had a habit of doing that if no one was holding the door. For the longest minute or so, he stood there, stark naked in front of his sister, who could only glare at him through half covered eyes with her hands on her face after giving up on rattle slapping his chest.

"Mike! Godammit! Get out and put some clothes on! Perv!"

Despite how distressed she was behaving to having a naked male family member in her room, a situation that was not normal at all, he could hear her voice wavering. It sounded a lot like fear, although Mike had no idea how he knew that. When he decided to come in here, he had no plan. It kind of felt more like he was following his cock instead, which soared in Judy's direction like tracker to a beacon. Precum was already oozing out of the excited head. It was fairly hard not to notice. Oddly enough, she made no move to edge away from him, her body turned and squashed together defensively in the middle of the room, as if she was hiding something. He soon realized from a strange scent that she was getting really wet, a circumstance from which he also had no idea how he knew. It was like his senses had heightened and he could pick up the slightest of changes in air.

"D-don't come any closer..." She was breathing hard, as if trying with great difficulty on holding something back.