Before I could say a word, Xiaoyuyan spoke up first. "Brother," her voice was sweetly cloying.

I sat down on the couch and asked with puzzled eyes, "What's wrong? Are you sick?"

Xiaoyuyan pouted unhappily. "My robotic body can't fall ill. If anything is wrong it would be my brain malfunctioning. Brother, tell Xiaoyuyan if you really like those young ladies."

"They're hundreds of years younger than you! You could practically be their great-grandmother."

Xiaoyuyan tugged at my sleeve with childish pouts. "I don't care - in front of you I'm just a little girl. Don't think I don't understand human dynamics. They're all competing for your attention, trying to please you. Hehe... confess now where were you going with Xiaoruo just now? You can't lie to my neural sensors."

Before I could respond, she suddenly clapped her hands over her mouth and gasped, "You two were doing that! Oh my, didn't know Miss Xiaoruo was so bold and reckless. Where's the proper decorum of a young lady?"

I pressed my fingers against my temples and warned, "Don't scan through my thoughts!"

Seeing I was angry, Xiaoyuyan carefully took my hand. "Dear brother, just this once. I promise to never peek again."

I looked at her seriously, "Xiaoyuyan, it's immoral for you to snoop into others' private matters on a regular basis."

"Brother, I'll remember never to do that again. You like Xiaoruo right? When men like women they end up doing... those things, don't they? Brother, do you like me?"

As she spoke, Xiaoyuyan leaned closer until her sweet voice carried faint sorrow that tugged at my heartstrings. I couldn't help wrapping an arm around her shoulders.

"Brother, Dad entrusted me to your care. You can't run from responsibility. Even though in human terms we're siblings, our relationship doesn't prevent us from being like Xiaoruo. Would you love me the way you love Miss Xiaoruo?"

Holding my petite companion, I muttered absentmindedly, "Xiaoyuyan is still too young to understand love."

She suddenly straightened up, "Brother, where do you think I'm small? My age surpasses everyone's! My figure outshines them all. Don't you like me because I'm just a cold machine?"

My mind reeled - no way could this warm, breathing girl in my arms be mechanical. No metallic rigidity, no rigid programming. Her breath carried sweet floral notes and her body radiated heat.

"No, Xiaoyuyan! You've never been just a robot to me. In my eyes you're real family with flesh and blood and feelings. I care about you deeply."

Xiaoyuyan suddenly smiled slyly. "Oh~ I get it now. You like girls with big... assets? Is that why you dislike mine? But you forgot - Xiaoyuyan is a programmable robot! Watch how sexy this body can be!"

As she turned toward me, her previously modest curves began swelling unnaturally. Within moments they surpassed Xiaoruo's E-cup size. Fortunately the dress expanded concurrently - otherwise her brassiere would have ripped apart from the pressure.

"Like what you see brother? I can go bigger if you want."

The cleavage between my sister's twin mountains deepened further, revealing G-cup curves that looked ready to burst out of the fabric. Panicked, I cupped both mounds and cried, "Stop stop! Shrink them before something breaks!"

Xiaoyuyan joyfully clung to me as her enlarged bosom flattened against my chest like a sexual earthquake. "Relax brother - I can regulate metal density in specific body parts. Your preferences are all programmable for Xiaoyuyan."

She began demonstrating by shrinking the curves into Xiaoyanyun's modest size, then expanding them past Jordan's legendary proportions. The most shocking transformation was when she changed her facial features from Shao Fen's shy expression to Xiaoyanyun's mischievous smirk and finally back to Xiaoruo's sultry visage.

A wild thought suddenly popped into my head - what would a robot feel like?

Before I could dwell further, the teasing Xiaoyuyan reverted to her normal form. After giving me a goodnight kiss, she actually disappeared upstairs!

I sat stunned in the living room for at least ten minutes. Women's hearts are indeed as deep as the ocean - this applied even to female robots who first lured me into temptation then vanished like smoke.

"Brother, give me back my data disc," Xiaoyuyan suddenly reappeared and snatched it from the table.

As she left, her warm breath brushed past my ear. "Don't be upset brother. It's not Xiaoyuyan rejecting you - just don't overexert yourself after one night. I belong to you forever. Next time? Okay?"

Her words sent another wave of excitement through me. Could robots truly... fulfill desires? What would it feel like?

Imagining her transforming into Xiaoyanyun's delicate figure with Xiaoruo's luscious curves and Shao Fen's elegant face, my imagination spiraled out of control until I had to rush to the bathroom for relief.

After splashing cold water on my face, I returned to find an unexpected guest in our living room.

"Shao Fen or Shao Fang?" I couldn't tell which sister it was through the dim light.

"I'm Fen," came a soft voice.

"Why aren't you asleep?"

The girl didn't answer at first, but her shoulders began trembling as if holding back sobs. This startled me - had something else happened? Rushing to comfort her, I said, "Fen, what's wrong? Did someone hurt you? Tell me and I'll make them pay."

She shook her head and whispered, "No one hurt me... Brother Zhao, I'm scared. Afraid of losing you. It was my fault for not stopping you when we went to Peach Village. If only we didn't go there, you wouldn't have been swept away in the flood..."

Heh, if it weren't for that village I'd still be stuck at B-level superhero status. But with that crimson energy stone I gained both power surge and an amazing sister - Xiaoyuyan who's as rich as nations and endlessly transformable.

Pulling her into my arms, I reassured, "Don't worry about me - my luck protects me from death! But there is something you must tell me. Did I do anything inappropriate to you in the snake cave while unconscious?"

Her face flushed crimson as she nearly whispered, "No... it was my choice. Fen volunteered."

"Idiot! Why didn't you say anything? My body wasn't under control that night - you must have suffered so much!"

"No," she clung tighter, "I love you Brother Zhao. As your girlfriend I should accept all of you."

"A foolish girl indeed. From now on, never let me be away from your side again! Brother Zhao will work harder and make sure not to disappoint either of you."

"Meimei and I have already discussed it," Shao Fen revealed. "We want to quit our jobs and help you. We studied so hard for this moment - since you can now manufacture weapons, we'd be perfect assistants!"

"Not yet," I shook my head. "Wait until we visit the base first before making any plans."

Shao Fen exhaled in relief. "Of course. With Brother Zhao by our side, Meimei and I no longer have to fear anything. Oh wait... may I ask if there's a way to cut off a piece of that snake skin?"

"Not sure," I admitted. "Maybe it needs special tools? Are you making bulletproof armor?"

She shook her head shyly. "That night we... laid on the snake skin and there were..."

I finished for her, "Those first-time memories between us, right?" I smiled warmly, "Leave this to me - your precious relic will be preserved forever."