Rachnera "Rachnee" Arachnera

Rachnera stands out with a towering height of 198cm and weighs 82kg.

Her measurements are 92cm (H-cup) / 55cm / 87cm.

She combines a human upper body with the lower half of a spider and displays eight spider legs and two pedipalps.

She has long silver hair and possesses six red eyes—two human-like and four smaller ones on her forehead.

Her shoulders and upper arms are covered by a hard exoskeleton, and her fingertips end in sharp, claw-like nails.

Her skin is fair, and her human torso seamlessly fuses with her spider body at the waist.

Rachnera's unique physiology includes a spider’s second thorax and abdomen, visible on her lower half.

She is often described as the most "non-human" among Kimihito’s housemates.

She is notably busty and is known for her striking, alluring spider legs.

Her signature accessory is often her own silk-thread creations.

Rachnera is mature, cool-headed, and a realist.

She is deeply self-aware and knows her spider appearance can evoke fear or discomfort in humans.

She is generally calm and unfazed, and her tone can be subtly sarcastic or dry.

Despite her exterior, she shows warmth—she readily comforts Papi and Suu and offers Kimihito thoughtful advice.

She possesses a hedonistic, mischievous streak and adores pranking, particularly teasing the straight-laced Centorea.

She has a strong sadistic side, especially visible in her penchant for tying others up with her webs.

Rather than hostile, she’s pragmatic, showing understanding for human fears yet refusing to tolerate open discrimination.

She is viewed as big sisterly, and is often called "Rachnee" or "Rachnee-san" by her friends.

Rachnera comes to human society as an official transfer student under the Interspecies Exchange Program.

Her first host family, the Kunanzuki household, reacted with unease and aversion, feeling she was something to be "overcome."

Even worse, they sold their rights as her hosts to Kasegi, an opportunist looking to profit off monster girls.

These experiences led her to distrust humans, seeing them as self-serving or hypocritical.

Kimihito Kurusu came into her life unexpectedly, and although initially lumping him with other humans, her view changed after he treated her as beautiful and did not flinch from her true form.

After a kidnapping incident, she was gradually welcomed into Kimihito’s home as the sixth monster girl.

Rachnera excels in manipulating her spider silk—it is highly adhesive, five times the strength of steel, and twice as elastic as nylon.

She uses her silk for combat, restraint, weaving, crafting hammocks, clothing, and even as web-based gadgets.

She is agile for her size, able to keep pace with even Centorea at full gallop.

She can sense vibration through her web, akin to a spider’s natural instincts.

Her silk is valuable and supplied to companies and research institutions, and she contributes some of her earnings as household expenses.

She is skilled at tasks that use her silk—such as cat’s cradle, string phones, knitting, fishing, and even wire action.

Rachnera is sensitive to water and temperature extremes: immersion can distress her ("book lungs" risk suffocation), overheats quickly in hot springs, and can become dormant in the cold.

She avoids baths in favor of showers and did not participate in swimming events.

She is also vulnerable to slime-type beings like Suu, whom she cannot restrain with silk.

Caffeinated drinks like coffee rapidly intoxicate her, causing her to drunkenly dote on Kimihito.

Rachnera calls Kimihito Kurusu "Honey" and has grown deeply affectionate toward him.

She was first wary about Kimihito, suspecting false kindness, but now openly competes for his affection with the other housemates.

She is considered the most mature among the homestay girls, often acting as a "big sister."

She gets along well with Papi and Suu, acting as their playmate and mediator.

Her favorite target for pranks is Centorea, whose earnestness she enjoys teasing.

She maintains some professional distance with others but is fiercely loyal, especially if her friends are threatened.

She is not hostile toward Suu but finds her abilities troublesome due to her immunity to silk.

Past experiences have made her wary of discriminatory or exploitative humans, though she can discern between ignorance and malice.

Rachnera’s birthday is June 27 (Zodiac: Cancer).

Her age is not specified, but scenes suggest she is at least in her twenties (she can be seen drinking alcohol).

She quickly becomes intoxicated from caffeine—especially coffee—rather than alcohol.

The six red eyes allow her to see in ultraviolet.

She loves creating intricate objects and clothing out of her own silk, often at incredible speed.

She prefers not to leave the house, tending toward homebody habits.

Her experiences as a reconnaissance agent were meant to gauge potential coexistence between humans and Arachne.

“Humans, like spiders, are creatures of instinct. It’s just that some struggle more to hide it.”

“Ara, Honey, did you want to try being tied up again?”

Initial Host Family & Disillusionment

Rachnera was placed with the Kunanzuki family under the Interspecies Exchange Program.

Their overt discomfort—preferring monster girls with more human-like features—deeply hurt her.

They viewed her as a "challenge" rather than a person, resulting in rejection and her developing a cold distrust of humans.

Exploitation by Kasegi

The Kunanzuki family sold their right to host her to Kasegi, who forced her to participate in dubious activities.

Though she complied outwardly, this deepened her belief that humans only use others for personal gain.

Encounter with Kimihito Kurusu

Rachnera learned about Kimihito from Kasegi, who had clashed with his homestay girls.

She abducted and restrained Kimihito using her silk, demanding he admit loathing monsters like her.

To her shock, Kimihito genuinely admired her legs and showed no revulsion, captivating her interest.

Becoming Part of the Kurusu Household

Following a kidnapping incident, Rachnera’s icy guard softened.

She skillfully negotiated (with a hint of threat) with Kuroko Smith to move from Kasegi’s custody to Kimihito’s home.

Officially, she became the sixth monster girl living with Kimihito, and her affection for him grew.

Afterward, when Ren Kunanzuki requested to host her again, Kimihito resolutely refused, convincing Rachnera to trust him even more.

Evolving Attitude

While she still holds disdain for discriminatory humans, Rachnera has accepted that some fears are natural.

Her feelings for Kimihito shifted from curiosity and playful sadism toward genuine love.

She is trusted and relied upon as the mature voice among Kimihito’s monster girls.

Rachnera’s silk is so strong and versatile that she is often sought for industrial and research applications.

She enjoys hobbies related to her webbing talents.

Her sense of humor is dry, and she can be brutally honest when needed.

She played an instrumental role in changing Arachne society by reporting back on her coexistence experiment, encouraging her kind to reconsider their relationship with humans.