When she looked at herself in the mirror, Trisha blushed. The nightie was innocent enough, but it was also very revealing. All of her milk-white, perfectly shaped legs were exposed. She could even see a hint of her pussy hairs peeping out under the short hem. Her big, firm tits jiggled freely under the fabric with every movement of her body, her big nipples forming noticeable bumps.

Trisha shut her door and padded silently down the hallway to her brother's room. When she reached it she saw that the light under his door was on. Ralph was probably up late, reading in bed. Trisha took a deep breath to compose herself. Then she opened the door and walked in without knocking.

Ralph was lying under the covers with the night lamp on brightly. His left hand held an open copy of a girlie magazine. His right hand was moving furiously beneath the blankets. Trisha knew she had just caught her brother beating off!

"J-Jesus Christ!" Ralph stammered. Staring wildly at his younger sister, he threw the girlie magazine to the far side of the bed and pulled the blankets up to his chin. "What the fuck are you doing here? God damn it, don't you fucking know how to knock! Jesus!"

"I'm sorry if I bothered, you, Ralph," Trisha said innocently, shutting the door behind her. "But it's so rainy out tonight, and I got frightened by the thunder. Can't I come in bed with you so I can sleep?"

Ralph said nothing. He was too busy staring at his younger sister's fantastic body. It had been many years since he'd seen her in her nightie, and Trisha knew her figure had developed considerably since then.

Ralph's eyes stared hypnotically at Trisha's big, jiggling tits, moving down her slender waist to her long, luscious legs. Under the blanket Trisha saw a tent forming at his crotch as his prick began to swell.

"Can I, Ralph, please?" Trisha said girlishly, approaching the bed. "The thunder's so loud, and I get frightened. Please?"