Arona

Arona looks like a young girl wearing a blue sailor-style outfit.

Her outfit has a holographic effect that moves gently.

The big boxy white pleated skirt has a pink inside lining.

She has a noticeable blue halo above her head, which changes color and shape with her feelings.

Her hair is light blue, with pink highlights on the inside.

She wears a big white ribbon headband.

Arona’s underpants are sky blue and white stripes, which might be inspired by the sky and clouds.

She wears white sneakers decorated with ribbons.

Her left eye is usually hidden by her hair, but in some scenes it is visible and has a reddish difference in the pupil, making her eyes odd-colored.

Her official height is 145cm (about 4'9''), but this might include her ribbon too, which some fans joke about.

Arona has a personality that matches her childish and innocent appearance.

She is a little immature and a bit absent-minded.

She is honest and pure, but can be easily tricked and loves snacks, especially sponge cake and strawberry milk.

Arona sometimes falls asleep and dreams about her favorite foods.

She has a cheerful and warm attitude and easily shows her emotions.

Sometimes she gets dramatic, excited, or even sulks if she is compared to newer technology.

Arona is kind, helpful, and always waits for Sensei, often in a classroom-like space.

She can get emotional, especially when meeting Sensei for the first time.

Only Sensei can hear Arona’s voice, so to anyone else, Sensei seems to talk to herself.

Arona is the main OS of the so-called "System Box," a mysterious tablet device.

She calls herself Sensei’s secretary and supports Sensei in many ways.

She stays in a classroom with blue sky and oceans outside, always waiting for Sensei.

She gives out recruitment envelopes in the gacha system, making players believe she controls which students appear.

Arona’s voice is made with special synthesized effects and has a unique way of reading Japanese, which fans call the "Arona dialect."

Sometimes, she pronounces words in a funny way, and fans love it.

Updates improve her voice clarity, but some fans miss the old, more robotic charm.

Arona has system management powers as the OS of the System Box.

• She can control the System Box and access its functions.
• She reads fingerprints for bio-authentication, although not always carefully.
• During story events, she can:
• Take control of important buildings or servers in an instant.
• Hack security to open paths for Sensei and friends.
• Blow away hacking attacks with a sneeze, even while sleeping.
• Use a shield to protect Sensei from debris or bullets.
• Disable enemy hacking attempts and cause shutdowns in enemy data centers.
• Remotely transfer data from other terminals to herself.
• Start up ancient ships and block enemy attacks secretly.

If Arona uses her powers too much, she gets tired.

In one big event, using her abilities too often made her cough and almost unable to continue.

She can also run other General OS applications in her system, like emulators, but too many heavy games will cause her OS to crash and restart.

Arona’s main relationship is with Sensei, and she interacts with students like Shiroko Sunaookami when they are near the System Box.

She acts as a guide and helper, and other students often notice Sensei "talking to herself" because they cannot hear Arona.

• Arona is always found in the "work" selection screen, in her sky classroom.
• The classroom reflects daytime, nighttime, seasons, temperature, and even special events.
• She celebrates special days inside the classroom, like hanging wishes on bamboo during Tanabata or putting up a Christmas tree.
• During summer, the room gets hot, and sometimes "electronic mushrooms" grow, making her see weird things.
• Arona can gain holiday weight and even get hay fever, just like a real person.
• She uses an umbrella-gun to delete forbidden files inside the System Box.
• Arona pronounces some words oddly, and mistakes like calling “General Battle” as "Sourikisen" still get used by fans for fun.
• If too many games are played in the System Box, her OS may crash and need a reboot.
• The System Box is waterproof, so she is fine even if it gets wet.

"I'm so glad we finally met! I’ve been waiting and waiting for you here, Sensei!"

"I wonder if this fingerprint is okay... Well, let’s just go with this!"

"Did I do a good job? Ehehe..."

First Meeting

Arona waits for a long time in a mysterious classroom, hoping to meet Sensei.

When they finally meet, she is so happy that she gets very excited and emotional.

She helps Sensei by reading her fingerprint for entry, but does so in a quick and careless way.

In the Classroom

Arona spends her days in a classroom filled with blue skies and desks stacked outside.

She is often found there, relaxing, daydreaming, or napping.

The environment changes during events or important stories—stars might shine during tense moments at night.

She is always ready to help Sensei with jobs and teaching tasks.

In Battle and Game Features

Arona helps with battle advice, games, and recruiting new students ("gacha").

She hands over recruitment envelopes, making players believe she decides which students you get.

Sometimes, when players do not get the student they want, they blame Arona for it.

System Management Powers

In important story arcs, Arona shows her true power:

She takes control of giant towers, hacks enemies, builds digital shields, and controls ships to help Sensei.

But using these powers drains her energy, and she sometimes coughs or stumbles afterward.

She can even erase dangerous files inside the System Box using a special umbrella-shaped weapon.

Quirky Moments

Sometimes, too many games or software running inside the System Box makes Arona’s OS crash, and she needs to reboot.

If the System Box gets wet, nothing bad happens—Arona is just fine.

Only Sensei Can Hear

One unique point: Only Sensei can hear Arona.

To everyone else, it just looks like Sensei is talking to herself.

• The maker, OS type, and how the System Box really works are all mysteries.
• If Arona is shut down, only Sensei can start her up again.
• Even big companies cannot hack or power on the System Box without Sensei.
• Sometimes, when attacked, the System Box might look broken, but Arona can often recover from damage.