yo i'm Okibimaru, pleased to meet you, i am a great lover of bleach and am very skilled in writing fanfictions for it (i'm not trying to brag it's just what iv'e been told)

Twin #1:
Name: Ira del Salvaje
Age(Appearance): Early 20s
Gender: Female
Hair: Dark, scarily like a longer version of Ulquiorra's. Comes down to halfway down her back.
Eyes: Blue, with a cat-like slit pupil.
Skin: Pale.
Mask: A small piece remains above her left eyebrow. It looks like the eyebrow of a chinese dragon.
Body build: Toned, but not overly muscular. She's more built for speed than strength. Her hollow hole is at the base of her neck.
Clothing: She wears a small tank-top under an open, short-sleeved jacket, and hotpants, all white. She wears black boots that come up to her calves.
Techniques:
1: Cero
2: Gran Rey Cero
3: Sonido
Zanpakuto form: Dual trench knives
Resurrección: Rabia del Dragón ("Rage of the dragon")
Resurrección appearance:
Looks like a white version of Red-Eyes Black Dragon. Both the claws and the front edges of the wings are metallic in both colour and nature, and are sharper than anything else in all of Hueco Mundo, the edges being able to glide effortlessly through the blades of zanpakutos. Her Arrancar face appears in the upper torso, right below the neck.
Resurrección techniques:
1: La Ira del Dragón Cero ("Dragon's Wrath Cero")
2: Garras de la Criatura Fabulosa ("Claws of the Fabled Creature")
3: Cola de borde de Acero ("Tail of Steel Edge")
4: Desgarrón (Yes, it's pilfered from Grimmjow, but she can't use it to its' full potential.)
Personality:
Ira's temperament is notably similar to that of Cirucci Thunderwitch; She has a tendency to look at things from a more childish point of view, but watch out for her temper: Unlike Cirrucci, Ira has a violent temper that's worthy of her Resurrección form. Most of the time, she's only interested in playing around with her opponents, but when she gets serious, her entire style of attack changes, although it should be noted that she almost NEVER uses her Resurrección. All in all, she has the temperament of a cat, with the moodiness of a dragon if angered. Unlike most Arrancar, though, she does have a notable soft-spot for her sibling, when he's not acting like (in her opinion) a jerk. She's the older twin, and loves rubbing it in her brother's face. She has a breast complex, since hers are so small (She's almost flat), and she doesn't like women with better 'endowment' than her. She really likes candy, and has given the Espada many a headache when she was on a sugar high. She has the spooky ability to eat and then burp back flames, much like Nel does with energy-based attacks.
Future event notes:
1: Ira steals candy from Yachiru in mid-battle with the Lieutenant, since she likes it so much. cue all other Shinigami taking shelter at Ikkaku's yelled warning.
2: Soi Fon makes a joke about how her lieutenant has bigger moobs than Ira cue all other Arrancar taking shelter, even her brother, and gets the shit kicked out of her for it.

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Twin #2:
Name: Furia del Salvaje
Age(Appearance): Very late teens
Gender: Male
Hair: Long, messy and golden, with green highlights.
Eyes: Red with a cat-like slit pupil.
Skin: Not pale, but not tanned, either.
Mask: On his right cheek, looks like a chinese-stylised tiger whisker.
Body build: Muscular and lithe, built with particular emphasis on ease of mobility and speed. His hollow hole is in the middle of his chest.
Clothing: Essentially the same as Grimmjow, just with short sleeves on his jacket.
Techniques:
1: Cero
2: Gran Rey Cero
3: Sonido
Resurrección: Tigre Ácido ("Acid Tiger" Yes, there is an accent over the 'a' in 'Ácido'. It's just really small.)
Resurrección appearance:
Largely similar to Pantera in design, but with sunny blonde and acid-green colouration in a stripe pattern. The claws are shorter, but thicker, and metallic in both appearance and nature. On the outside edges of the hands, small blades run up the tendons, like spines. The tail is tipped with a metallic spine about 5 inches in length (Kind of like a Kut-ku). Both the claws and spines (hands AND tail) are poisoned. The poison is heavily acidic, hence the name. In addition to a head crest like the one on Pantera, Tigre Ácido's mask also has spike-like whiskers framing the side of Furia's face.
Resurrección abilities:
1: La Sed de sangre del Tigre Cero ("Tiger's Bloodlust Cero")
2: Garras de la Criatura Fabulosa ("Claws of the Fabled Creature")
3: Desgarrón (Yes, it's pilfered from Grimmjow. Unlike Ira, Furia CAN use it to its' full potential.)
4: Cambio Repentino ("Sudden Shift" Like Shunpo, Sonido, and Hirenkyaku, it's pretty much an instantaneous movement technique. Unlike them, though, it has increased range, and is a teleportation technique without most of their weaknesses, since it can't be intercepted halfway, leaves almost no trace of its' use (including sound), and there is only one way to tell where the user will appear next (the user must have eye-contact with their intended destination). Furia later comments that the technique uses enough Reiatsu to forcibly spawn a Gillian from scratch. Ira doesn't use it, making this technique truly unique to Furia. Furia doesn't use it much.)
Personality:
Unlike his sister, Furia is a relatively friendly and easy-going character. He doesn't harm anyone unless he's given motivation to do so, unlike most Arrancar. He is, however, fairly easy to motivate towards a battle if someone pulls a zanpakuto on him. Since he likes to take the path of least resistance at most (if not all) times, Ira often has to forcibly motivate him, often being heard to literally shriek insults at him (or launch Cero variants at him, depending on her mood). Unlike his sister's short fused temper, Furia is only rarely seen irritated, much less angry. His temperament changes dramatically once he's actually drawn into a battle though; he becomes aggressive, moody, and any number of other unpleasant emotions for a short time after any battle, and actually in battle he's nothing short of emotionless, making ruthlessly precise moves and strikes to bring his opponents down hard, and in most cases permanently. He spares the few he either needs for the twins' plans, or respects. Out of the twins, he may be the most laid back, but Ira knows well enough that Furia is the more rational of them.
Future event notes:
1: When Furia meets Shunsui Kyoraku and Jushiro Ukitake, all three develop a great deal of respect for each other. Commonly, when Furia can't be bothered to join a battle, he and Shunsui sit on the sidelines, sharing sake and generally just getting along. He, at one point, calls Shunsui "Possibly the greatest drinking partner the worlds have even heard of", much to his sister's irritation.
2: Furia can also 'sleep-fight' quite well. During one particular episode of his sleepwalking, he takes on the top three Espada by himself when they ambush him. Since he's more motivated in his sleepwalking state, the Espada quite promptly LOSE the 3-on-1 fight.
3: Although they begrudgingly respect him, the Espada quite simply don't like him. He parries more attempts to strike him from behind on any one given day than the entire Espada did when Aizen was in the top spot.
4: When asked by Shunsui about which twin is the 'evil one', he reponds with "Yeah, about that... We're still trying to work it out, too..."