Chapter 1

My name is Sophie Cheng, a 23-year-old accountant, and I have a story to share. This incident occurred last year during our family's annual Christmas party. After my parents divorced at a young age, my father gained custody of me due to my mother's financial issues.

My father, a very eligible bachelor, remarried shortly after when I was eight, to a younger woman who was also a divorcee. She brought along her cute and obedient son, Max, who was four years younger than me. After the marriage, they moved in with us.

Growing up, Max and I were unaware of the complexities of the adult world. We bonded instantly and got along well as siblings. He has been like a real younger brother to me over the years, even calling me 'Zeh Zeh,' which means elder sister.

My stepmother treated us equally, and I grew to love her more than my distant mother. Life in our family felt normal, and I felt blessed and grateful that my father did not have to raise me alone, providing the warmth of a true family.

I have often been told that I resemble the K-pop singer Hyuna. With measurements of 32C-24-33 and a height of only 1.65m, my voluptuous assets make my body appear even curvier. My round proud breasts and firm perky butt often attract a lot of unwanted attention.

Men at both my university and current workplace frequently give me weird and piercing stares, and I have caught several of them gawking lustfully as I walk by. Despite all the attention, my busy work schedule has prevented me from finding a boyfriend.

Every year, my parents organize a party on Christmas Eve and invite everyone they know. The house is always packed with guests, offering food, drinks, and games for the kids. Due to the large number of attendees, Max and I usually exclude our own friends from the party. Last year, my stepmother suggested we do something different, like a costume party, which was a welcome change from the usual Christmas routine.

A week before the party, Max came to me anxiously. He had purchased a four-armed monster snowman costume from eBay but hadn't paid attention to the details. When the costume arrived, he realized it was designed for two people.

Returning it was not viable due to the hassle and shipping costs. Knowing I hadn't bought my costume yet, he begged me to be his costume partner. Initially reluctant because I didn't find the monster snowman design appealing, I agreed after realizing he had no one else to turn to but his trusted elder sister.

Christmas Eve finally arrived. Due to the stuffiness of the costume, deciding what to wear underneath was challenging. Max opted for a singlet and boxer shorts, while I chose my flimsiest T-shirt and a pair of FBT shorts.

Since Max was slightly taller than me, I took the front position to ensure my vision wasn't obstructed. This also meant I could go braless without Max noticing. Disliking even the slightest heat, I decided to forego underwear as well, naively thinking it would cause no issues.

Before squeezing into the costume, we made sure to empty our bladders, as getting out of it would be difficult. I'm not sure if Max was aware that I wasn't wearing any underwear, but I assumed it wouldn't be a problem for him.

We slipped our arms and legs into the four-armed snowman costume, which was unexpectedly tight due to its foam construction and lack of interior space despite its round and bulky shape. My back was pressed tightly against his torso. It was then that I became acutely aware of the front of his boxers against my butt, feeling his limp manhood pressing into my left butt cheek through our shorts.

I thought nothing of it initially. After all, Max was my younger brother, and I should have anticipated this the moment I agreed to share a costume with him. Walking in the costume wasn't much of a challenge; we simply needed to synchronize our steps.

We practiced a bit before the guests arrived, and we were quite pleased with our teamwork and coordination. All the while, we kept cool under the air conditioning. As evening approached, the guests began to arrive slowly.

My father asked us to stand at the door to welcome the guests as they entered. We greeted everyone and handed out candies to the children. After about an hour, it started to get warm inside the costume. I had begun to sweat, and so had Max.

I could tell because our thighs were skin on skin, and the sweat between us made it sticky and slightly uncomfortable. Consequently, Max began to fidget in the costume, much to my dismay, as I didn't appreciate how his front kept rubbing against my back.

I tried to ignore what he was doing behind me, but his movements only generated more heat inside the costume. I could feel his crotch pressing repeatedly against me. Having had boyfriends in school, I knew the signs of an erection. Max's fidgeting was not helping the situation. I tried to act normal and didn't want to point it out to avoid embarrassing him.

While handing a candy bar to a little girl, I bent forward slightly while Max remained upright. This caused the tight costume to stretch as we pulled in opposite directions. When it snapped back, my butt jammed back onto his crotch, and his erection slipped right between my butt cheeks. We both fell silent in this awkward predicament. Damn it, I could feel it rubbing against me with every slight movement we made.

Before we knew it, the guests were really streaming in. We struggled to keep up with the greetings as children ran circles around us, eyeing the candies. The guests wore various costumes, some lame and some creative, but none particularly eye-catching.

All the constant turning and twisting in the costume, while trying to coordinate our steps, worked against us. Our practice hadn't prepared us for this influx of guests, and it was getting increasingly hotter inside. In the midst of it all, Max stopped his constant fidgeting, which was odd.

Then I realized I had a semi-erection between my butt cheeks, and it seemed to be hardening. With the number of people we had to attend to, there was no escaping this situation, so I secretly hoped that his erection was due to the heat and that we could cool off under the air conditioning once the last of our guests had arrived.

Max attempted to turn to his side to ease his semi-erection out of my butt cheeks but did not succeed. He then bent his knees slightly to lower himself and find space to maneuver. This caused his dick to slip from my butt crack, rub along my cheeks, and spring up beneath my shorts. To make matters worse, the thin strip of cloth covering my naked pubes was dangerously exposing my privates to his still-hardening dick.

He realized this too. His breathing quickened behind me, and I could feel his heartbeat furiously pounding against my back. Our only option was to remain very still, and I had to squeeze my thighs together as tightly as possible to prevent his erection from rubbing directly on the bottom of my shorts and accidentally making contact with my naked pussy.