He tells her the truth

Robin pauses a moment to confirm his suspicions. He runs his hands gently up her tummy, up the invisible fabric, untill he hits what feels like a hidden underwire just below her cleavage. "I think... Either I have xray vision. or..." He trails off, following the underwire out to the sides of her curves with each hand. "...or you've made your clothes invisible."

Sophie scoffs at first. . Robin was sputtering utter nonsense. That wasnt real, she could see her clothes with her own eyes. "Are you saying you can see my underwear? What color is my bra?" she asks mockingly, nodding to his hands on either side of her bra area.

"I'm saying..." Robin gulped, face growing even redder than hers, "that you've somehow made ALL your clothes invisible." With that he gingerly poked the sides of her visible breasts, confirming for certain that there was a stiff bra material between his fingers and her soft, supple boobs. Inadvertantly, that also caused them to bounce in a very conrolled little jiggle. This illicited a little gasp from each of them simultaneously, though for very different reasons. That seemed to be just the thing to break through to her though. He could see the wheels turning in her mind.

With a face turning reder by the second Sophie pulled her arm across her chest. Holding on to some hope, she tested him. "If my clothes look invisible to you, which boob is bigger?"

"Uhhh..." Robin stuttered uncomfortably. "I honestly cant say Soph. Ive been trying my best not to uh... stare... as much as possible. They look about the same, really." He says, stepping back and glancing at her with a noncommital shrug.

Sophie, wanting this to still be a prank, and for that prank to be over, thinks for a second and asks amore confidently, "Okay, if you can see me naked, how much body hair do i have down there?" With that, she nods triumphantly for him to look at her mound - which she can see is well covered in layers by her panties, shorts and a long thick robe.

Robin scratches his head, leaning down and pushing his glasses up his nose to get a slightly better look. "Err... well... uh Soph..." he stutters, "I was going to say that you shaved. At first it looks bare as a baby down there. But up close im actually seeing tiny whisps of blonde hair - not alot - that naturally just blend in. Wait. Sooo... you're not a natural brunette?" The implications of that small revelation seem to momentarily distract him.

Sophie jumped! At least a foot in the air. She clapped a hand between her thighs, squealed loud enough for the neighbors to hear, and ran for their room as fast her her bare legs could carry her. She slammed the door behind her, leaving a red faced Robin alone in the room.

"Shit!" He thought, "We need help." With that he whipped out his phone and tried calling Viki. Where was she? No answer. Finally he tried calling the only person he could think of. After a moment, "Hey Harvey? Can you come over please? Sophie needs our help."