My Ex-Girlfriend’s Sister Ran Away to My Room, and We Can’t Stop Making Mistakes. - Chapter 12: Growing Up Fast.

Growing Up Fast.

The shop Mii wanted to visit was located just past Hachiko Square, across the Shibuya Scramble Crossing. As the lights changed and the mass of people surged forward in unison, Mii let out a soft “Whoa.”

“There really are a lot of people. It’s almost stupid.”

“I don’t know if I’d call it stupid, exactly.”

“Maybe not.”

We moved along, caught in the slipstream of the crowd.

“Where is this place you want to go, Mii?”

“Wait. I’ll give you the address.”

I typed the location she provided into my smartphone.

We cut through the area near Parco, navigating the narrow gaps between buildings that pressed in from both sides like rising waves. Since this was her first time in Shibuya, Mii’s head was constantly on a swivel, taking everything in.

“It’s different from Shinjuku. The roads are narrower… it’s more cluttered.”

“And there are a lot more hills.”

“Also, it smells a little.”

She scrunched up her face, pinching her nose. Tucked away in a multi-tenant building off the main thoroughfare was the apparel shop she had been looking for. A weathered brown sign hung on the second floor of a vintage building.

“I found it on Insta. This brand is only in Tokyo.”

Despite the aged exterior, the inside was stylish and bustling with customers. A female clerk folding clothes offered a polite “Welcome,” and Mii gave a small nod before stepping inside.

“I brought my coat, so I want a skirt and a shirt.”

As she began browsing the racks, Mii’s eyes lit up with genuine excitement. It was the first time since she arrived in Tokyo that I’d seen her look so… lighthearted.

She used to be a girl who laughed a lot. She would laugh out loud at even my most trivial stories. Seeing her pick out clothes now stirred a sense of endearment in me.

“Maybe I’ll try this on.”

Clutching a pale pink long skirt and a gray sweatshirt, she headed toward the fitting rooms.

I took a seat and waited. After a while, the fitting room curtain slid open. Having changed into the new outfit, Mii stepped out and showed me, her movements a bit stiff with self-consciousness.

“Hey, what do you think?”

The spring-like colors gave her a much brighter aura than her usual school uniform. She did a little twirl in front of me.

“The size feels right, but…”

“Yeah, it looks good on you. It makes you look more grown-up.”

“Really? It doesn’t make me look fat?”

“Not at all. You’re fine.”

She hummed thoughtfully, agonizing in front of the mirror for a moment before nodding as if she’d made up her mind.

“Okay, I’ll take these.”

She had the clerk remove the tags right there and stayed in her new clothes. As she reached for her own money, I stopped her hand and pulled out my wallet.

“I’ll pay.”

“Are you sure?”

“I have the money. I just don’t usually spend it on anything.”

Mii tilted her head, looking conflicted, but after realizing how thin her own wallet was, she offered a reserved, “Thanks.”

“I’m just happy you came shopping with me.”

“Don’t you want to buy anything else?”

“No, I think this is enough. I’ll get the rest of what I need at Uniqlo or GU.”

“You don’t have to hold back for my sake.”

“It’s not that. You only need one truly special outfit.”

Looking pleased, she stepped out of the shop and spun around to face me.

“Hey, I’m hungry.”

“It’s a bit late, but let’s grab lunch. What do you want to eat?”

“Well, I was thinking—”

As she started to speak, a group of high school girls about Mii’s age walked by on the opposite side of the street. They likely attended a school nearby. Still in their uniforms, they passed us laughing, chatting brightly about whether they should go to karaoke.

Mii suddenly fell silent, her body stiffening as she watched them walk away. In an instant, the light vanished from her face, replaced by a heavy shadow.

“Hey, Mii.”

I called out to her as she stood frozen.

She didn’t react.

“Mii.”

The group of students rounded a corner. Only then did she blink, snapping back to reality and turning toward me.

“Did you say something?”

“Look… don’t you actually want to go back? To just go to school like a normal person?”

“I don’t.”

“But you should at least graduate high school. Things are easier if you do. It can’t be all bad.”

“It is all bad.”

“You’re in your teens. It’s probably easier if you keep your options open. I’m sure of it.”

“No. I won’t.”

This time, her denial was loud. She let out a sharp breath to steady her breathing before continuing.

“I hate that. ‘Because you’re in your teens’—I hate that kind of talk.”

Her words were laced with thorns.

“It feels like people are telling me that this is supposed to be the best time of my life.”

“Isn’t it?”

“That’s what they say. It’s stupid. For someone who can’t enjoy it, a ‘golden youth’ is nothing but a curse.”

She bit her lip hard.

“I want to grow up already.”

Watching the corner where the high school girls had disappeared, Mii spat the words out.

Years ago, her sister had said the exact same thing. When she had confessed to me that she wanted to grow up fast, she had worn that same expression of unbearable frustration.