Michelle's birthday started normally, but her stepbrother's forgetfulness sparks an unexpected, kinky twist. Catching her in the bathroom, he's greeted by her naked form, a vibrator in hand. He apologizes, presenting her with a unique birthday 'gift': his throbbing cock. She's hesitant, but her curiosity and lust win out. She takes him in her mouth, feeling him grow harder, then mounts him, riding him slowly at first, then faster, birthday girl ecstasy written all over her face.