Musubi

Height: 161cm
Weight: 48kg
Three size: B 97 / W 58 / H 89

The heroine. Minato's first Sekirei. She met Minato when she fell out of the sky. She is a power-Strength-type Sekirei. After hearing Tsukiumi say that she is Minato's wife she decides that she is gonna be his wife too. She is very naive and often says things she does not understand. She also eats a lot. At times she has a ferocious bear appear behind her, which didn't actually appear until after she became Miya's disciple.

Personality
Musubi is very naive, positive and insightful, often says things she does not understand, and is probably the most 'childish' of Minato's Sekireis, even more so than Kusano. She is, however, very eager when it comes into confronting other Sekireis (to the point where her eyes gleam and sparkle at the prospect of fighting another) but never fails to be polite as she would usually asks for permission first before fighting them.

Abilities and Powers
Musubi plays a crucial part in Minato's team and is always seen participating in Sekirei battles due to her desire to fight strong opponents. Musubi's abilities are hand-to-hand combat which utilizes her greatly enhanced strength. This is enforced by the heavy combat gloves she always wears. Her attacks and techniques are mostly punches and kicks which are supported by her ridiculous strength.
Something else notable about Musubi is that she also has a good amount of stamina and endurance evidenced during her first fight with Benitsubasa. She took several hits during that fight and was still able to stand up to Benitsubasa's surprise who thought that she went down after one hit. Even the Disciplinary Squads Ashikabi acknowledges her strength and came to the conclusion that Benitsubasa would have a hard fight against her without using her Norito.
(Source: Wikipedia, Sekirei Wikia)