After Reaching the Happy Ending, I Was Locked up by the Extremely Possessive Heroines I Had Conquered

Chapter 3.1: From My Stepsister’s Conquest to Her Yandere Transformation

When I was reincarnated on this island, the first person I met was Mahiru.

She’s my stepsister—not bound by blood, but living together with me on this island where our parents are absent.

She’s one of the main heroines of ‘Black Tide, Great Serpent, Island of Prayers’. With her lovely appearance and reserved personality, she was a character who captured players’ hearts. But her fate was far too cruel.

In the original story, Mahiru faced discrimination from the islanders because of her outsider blood. While her mother was from the island, her father was not, making her an outcast in their eyes.

In such circumstances, her brother was unreliable, leaving her tormented by loneliness. Ultimately, she took her own life at the edge of a cliff.

Her death was dismissed by the islanders as the result of her “outsider blood,” and the truth was buried, leading to a gut-wrenching bad ending.

In the original story, by gradually building relationships with the islanders, the discrimination could be eased. Mahiru could forge a bond with her brother, both as siblings and as something more, escaping her loneliness for a satisfying conclusion.

Her courage in confronting discrimination head-on and carving out a place for herself was inspiring, and I thought it was a fulfilling ending.

However, reaching that route took time and meant you couldn’t save the other heroines.

So, I decided to save Mahiru from her loneliness in a different way. My strategy? Relentlessly engaging with her.

At the start of the story, our sibling relationship wasn’t great. We barely talked, living like strangers under the same roof.

So, my first step was to strengthen our sibling bond. I wanted to be her true family, her ally, even if the islanders discriminated against her.

—I’d never let her feel alone.

With that resolve, I threw myself into interacting with her.

For example, one early summer day, I faced Mahiru in the living room. She was at the table, silently working on her homework, her eyes gazing somewhere distant, certainly not at me.

“Hey, Mahiru, wanna go for a walk after your homework? I heard there’s a sea turtle at the nearby beach.”

I spoke brightly, maybe a bit exaggeratedly.

“I’m not interested,” she replied coldly, not even pausing her pen. The discrimination from the islanders had likely closed off her heart, and she kept her distance from me, her stepbrother, to protect herself.

Despite her indifferent attitude, I knew from the original story that she loved animals. She had to be curious about that sea turtle.

So, I didn’t give up.

“Alright, how about I grab some ice cream instead? Want some? You like chocolate, right, Mahiru?”

“Don’t decide what I like.”

“But you do like it, don’t you? I saw you happily eating chocolate the other day.”

“Tch, that’s…”

Mahiru’s cheeks flushed with embarrassment.

“You’re so annoying. You’re mean, Akira,” she said, glaring at me resentfully.

It might’ve seemed like she was pushing me away, but her glare meant she was looking at me.

“First time we’ve made eye contact today,” I teased.

“Ugh, shut up!” she snapped, her eyes meeting mine for just a moment. That small change gave me hope.

From then on, I pestered Mahiru relentlessly. In the mornings, I barged into the kitchen to make breakfast together, getting scolded when I suggested adding chocolate as a secret ingredient to her omelet.

At school, I invited her to lunch so she wouldn’t be isolated.

After school, we watched the sunset on the rooftop or walked home together, even if she didn’t want me to.

I made sure to always be by her side.

Of course, she rejected me at first.

“Akira, just leave me alone!”

“I like being by myself!”

“Stop following me!”

Her rejections came again and again. She glared at me, insulted me, pushed me away countless times.

She never once called me “big brother.” It was always “Akira,” like I was a stranger. She probably didn’t even consider me family.

But that wasn’t enough to break me. For a happy ending, a few hurts were nothing. I was ready to take a punch if it came to that.

So, I kept at it with a smile, sometimes forcefully.

About a month later, on a cliff Mahiru loved, I smiled gently at her.