Hikari and Hibiki

Hikari is tall with a slender, yet quite curvaceous build. She has long black hair that she wears in two ponytails and narrow hazel eyes. Despite being Hibiki's twin sister, there is a notable physical difference between the two, in that her bust is significantly larger than her sister's (Hikari's bust is of similar size to Tsukiumi's, while Hibiki's bust is barely larger than Benitsubasa's).

In the anime Hikari wears a violet or blue bodysuit (a darker one in the manga), in addition to dark boots and gloves matching the colour of the bodysuit. Minato briefly describes the twins' attires as similar to BDSM gear when referring to them. She also takes some pride (and is somewhat embarrassed) at the fact she has such a large bust (she's actually an E-cup)

As for Hibiki, she is tall with a slender build. She has long black hair that she wears in two ponytails and hazel eyes. Despite being Hikari's twin sister and looking exactly like her, the only physical difference between the two is that Hibiki's ass is more round and shapely. Her breasts are even the same size, E-cup.

In the anime Hibiki wears a pink bodysuit (a brighter one in the manga). Minato often referred to the sisters in the beginning of the series as the "Onee-chans with S&M clothes".

As for their personalities, Hibiki is the more calm and level headed of the group when it comes to fighting against other Sekireis; even her own sister. Whereas Hikari is more passionate and fights wearing her emotions on her sleeve. Both Sekireis however always are up for a chance to bond with their Ashikabi... especially if it leads to some rather lewd and naughty moments (Hikari gets embarrassed but easily submissive and Hibiki is similar in that she's shy but no less lewd than her sister.) And from time to time they even love dominating their Ashikabi.

As for how they fight, they both use lightning based techniques to fight and are especially powerful when they combine their powers. Their Norito, "God's Song" causes a massive bolt of lightning to crash on their enemies without harming their loved one and when casting it they chant "By the Thunderclap of our Pact; all our Ashikabi's enemies will be destroyed!"