In this story nobody under 18 is mentioned in sexual connotation.
...
"Fran, don't you think it's going to be better if we help her with money?"
"No. In her desperate situation, she needs much more than just financial support. She needs emotional support and love from her closest relatives. I don't understand your reluctance; on multiple occasions you told me you two were buddies growing up."
"It's true, but now you and I are married..."
"So what? We'll have our bedroom, and she'll stay in the guest room until her mental status improves and she starts dating again."
"...OK..."
"Thank you, Walt. I knew you were a good man and would not disappoint a family member in need."
I remained quiet.
...
My younger sister Nora and I grew up in a modest home. Dad was a low-wage factory worker, earning little. Mom found additional work as a part-time taxi driver. Our house had only 2 bedrooms. Our parents lived in one, and my sister and I in the other. The 3 years difference was enough to prevent rivalry, and as the older, more responsible sibling, I helped her with homework.
The arrangement worked beautifully until puberty. But later, we had several embarrassing episodes and I hung a large sheet in the middle of the room to create some privacy. This improvisation seemed to make things better for a while.
Due to our limited resources, when time came, I attended the local state college for free, preferring to sleep at home rather than in the dorms.
Nora looked like any other girl until puberty: Average height and weight and unimpressive face and body. However, over time, she changed for the better. I was so used to looking at her as 'my little sister' that the changes escaped me. One day, Travis, my best friend, said my sister, who turned 18 three months earlier, became 'hot.' We laughed together and soon moved to talk about sports.
The next day, I returned home early and caught Nora walking to our room after the shower in her underwear. I was stunned. Her wet blonde hair was wrapped in a towel, and her cosmetic-free face looked... cute. However, my attention was focused on her chest. Her tits were huge and were especially noticeable on her short stature and narrow waist. My penis stiffened, and I rushed to the kitchen to prevent her from seeing it. The same night, I dreamt about seeing her strolling to the bathroom naked. I came in my briefs...
A week later, I was looking for my favorite pen Nora borrowed the evening before. She wasn't in the room. I opened 3 of her drawers, and at the bottom of the lower drawer, I found her diary. I knew some girls had a diary, but I was amazed to see she wrote it rather than typing it on her computer. I couldn't resist and read the latest pages. She mentioned being in love with an anonymous guy she called W, who had no idea about her feelings. I tried to guess if It was Warren, who was on their football team, or Wesley, the best student. In the following days, her voluptuous figure popped frequently before my eyes, often at bad times, like during class or when friends talked to me.
It all changed after I promised Nora to help fix her broken shelf. I was too busy and forgot about my promise. Then, the next day, I had free time and snooped again at Nora's diary. The sentence that caught my eye was, 'W used to be so nice to me before. Nowadays, he hardly notices me. Even his promise to repair my shelf was forgotten. I love him, and my chest hurts so much...'
The same evening, I apologized for not taking care of her shelf earlier and restored it. She thanked me and kissed my cheek. I said, "You don't need to thank me. I am your older brother, and I love you."
She mumbled, "Do you?..."
I said, "I really do, but I do not feel comfortable talking about it."
She smiled, "Why not?"
I blushed, "You are all grown-up, pretty, and look like a pinup girl. But you are still my sister..."
She approached me, hugged my chest, and leaned her head on me. She whispered, "Walt, I love you too..."
Nora's massive breasts pressing against my body awakened my pecker, which hardened in no time. I tried to separate our lower bodies, but Nora refused.
I caressed Nora's hair and murmured, "Sis, you are playing with fire."
She didn't let go and gazed into my eyes with half a smile. She whispered, "Chicken..."
"Nora, please, let me go before I do something we both regret later."
Her eyes concentrated on mine, "Do it!"
I kissed her luscious lips tenderly. She parted her lips and invited my tongue into her sweet mouth. Our French kiss lasted about a minute before I separated our mouths, "Damn you, Nora. You are too sexy for your own good!"
She faked innocence, "I have no idea what you are talking about." She half closed her eyelids and arched her back forward. The bulge in my pants became too apparent.
Nora smiled, "It's nice to see that for once you DO notice me... Do you want me to help you with your... prominent problem?"
My body craved to have her, but my brain tried one last time, "Please, you are my sister... You don't wish to lose your virginity to me."
She grinned, "Bro, on my 18th birthday, I tried to interest you, but you were watching football with Travis, so I fucked Josh. He always had eyes for me. I never cared about him, but he was available, and you were MIA."
I just stood there, my eyes hypnotized to hers. Nora's fingers fumbled with my fly. I was frozen. She knelt on the carpet, freed my erect cock, and caressed it lightly, whispering, "At last..."
Her lips enveloped my cock, and she began bobbing on it. My brain woke up, and I pushed her away, "Nora, please, let's think about it before committing an incest."
She smiled, "I think you are too stubborn for your own good."
"Maybe, but I am the adult one."
"We'll see. In any case, I always hated the separating sheet." Next, she removed it, stretched her arms up, and said, "I am going to sleep." Subsequently, she removed her blouse and skirt and remained in her bra and panties. She went to the bathroom to freshen up.
I took the opportunity, undressed except for my briefs, and entered my bed under the thin blanket. Unfortunately, my tumescent pole refused to shrivel.
Nora entered the room and immediately noticed the tent in my groin. She lifted my blanket and joined me in my bed, "Walt, I am no longer your little sister. I am the one who caused your organ to react favorably, so stop the nonsense and kiss me."
I gave up. I French kissed her hard for a long time, taking her breath away. After a pause to catch her breath, she mumbled, "Good boy. Now, unclasp my bra. I want to feel your hands on my boobs."
With trembling hands, I released her bra. Her magnificent round tits swayed gently before my eyes, displaying large pinkish areolas and darker hard nipples. I cupped both lovingly and kneaded them lightly. She sighed, "I wanted it for too long. I am so wet. May I suck you?"
"No. I am afraid to cum too early if you do it. I want to taste your nectar."
"OK, but even if I climax during your oral, I still wish to feel you inside me..."
I moved between her spread legs, kissed her lips softly, and descended to the side of her neck. She shivered, "I am so horny..."
I continued down to her glorious tit and sucked on it gently. It was delicious, and I milked it harder. Nora murmured, "Honey, my breasts are very sensitive. I am ready. Please put it inside me."
I removed her panties, aimed the spongy head toward her opening, and penetrated gingerly in. Her pussy was extremely tight but well-lubricated. My advancement into her womb was slow and steady. Nora's pulse increased gradually the deeper I went. Once I was all the way inside her vagina, I started drilling it.