Kasumi is fairly sweet, but somewhat introverted. She prefers approaching situations from a tactical and thoughtful perspective. Her fighting style is also very calculating, and during fights her mind is constantly running with counters to her opponents' possible moves. She channels the Legendary Alliance--Saint Viktor and Archemorus--to heal her friends and bolster their attacks while also dishing out fierce attacks.

Kasumi and Shiori fought against each other in the Dream, constantly going at each other's throats in vicious duels. They brawled in a great green plain, a land not of grass and soil, but of jade. Names floated by on the wind. Strange names. Exotic names. Water pooled in the jade where the Sylvaris' battle had chipped off pieces.

They both awoke at the same time as Sylvari of the Day. As soon as they awoke and discovered that they in fact had the same Dream, they became incredibly close friends immediately, to the point that they refuse to be separated. Their brawls in the Dream meant that each knew the other's fighting style incredibly well, making them a force to be reckoned with as a fighting duo.

Their names are references to Cantha, a far off land that the two girls had both dreamed of. They were both bestowed upon the same exact Wyld Hunt, to visit the Jade Sea, though they knew not what their purpose was. It is unknown how knowledge of this far-off land made its way to the dream, but it is presumed that it entered by way of other Sylvari who are part of the Durmand Priory.

Kasumi and Shiori appear as identical twins due to the fact that they were born from the same pod, and both share the exact same Wyld Hunt. As such, they were once thought to be twin sisters. In reality, all Sylvari born from this Pale Tree are brothers and sisters, and are free to choose lovers as they wish.

Despite being born from the same pod, Kasumi and Shiori have drastically different physiological differences, such as skin color, ear shape, body shape, glow color, etc. These differences emerged as part of their unique personalities. Yet despite these differences in their bodies, they both chose to retain the exact same facial appearance, which is the reason people keep mistaking them for twin sisters.

The twins' home of Caledon was the target of many Risen attacks, and so the two founded a guild called the Rose Vanguard in order to gather powerful members to help fight the Risen. Their first member was Basil, a Soundless Sylvari necromancer. The guild was short-lived, as they undertook only a handful of missions before Basil left the guild to pursue her studies at the Durmand Priory, which caused the guild to fall apart. However, in the wake of Mordremoth's awakening, the guild was reformed, this time with extra members.

Kasumi and Shiori are currently trying to get to Cantha to complete their Wyld Hunts. Based on their research, the twins believe that they may be a small part of a much grander story set to take place there.

Kasumi specifically had dreamt of a strange weapon. It appeared similarly to a weapon that Belinda, sister of Marjory, had once wielded. Shiori recited this design to Dazzu and Ella, chief engineers of the Magitek division of the Rose Vanguard. They were able to create a duplicate of Marjory's weapon, which Kasumi wielded with a mastery not seen among other revenants. Kasumi then became Tyria's first ever Vindicator.