Kasuga

Kasuga is a fictional ninja introduced in Sengoku BASARA.
Kasuga was sent on a mission to kill Uesugi Kenshin. However, when she had her target in sight, Kasuga fell in love with Kenshin. After failing to assasinate Uesugi she was banished from her village. From then on Kasuga served Kenshin and became his most loyal ninja. She takes her duties seriously, and due to the Kenshin's battles with Takeda Shingen (as well an implication that they are from the same ninja village) a rivalry grew between Kasuga and Sarutobi Sasuke. Additionally, the two ninja have opposite elements.
She is often seen as having a rivalry with Nōhime as well, due to the other woman's role as Nobunaga's love interest and protector, and their similar personalities.
Kasuga although is very beautiful, she is noted to have a very sexual appearance, with a skin-tight body suit that's open very low in the front, baring half of her breasts and some of her legs.