Ayano Kosaka is a female member of Ryo Sayama's unknwon terrorist group and is skilled at martial arts. She first appears in Code Geass: Akito the Exiled where she tries to abduct General Smilas but fails and joins the W-0 Special Forces of the European Union. She is always practicing Japanese martial arts and carries around a wakizashi.
Very little is known about Ayano's past however she seems to have an attachment to her wakizashi. She first appears when Ryo is planning to attack an EU convoy using a Glasgow hacked by Yukiya Naruse and uses a grenade on the General's vehicle to force him out. She then knocks him out to deal with Leila but is subdued by her and is forced to the ground and is soon relieved of all criminal charges in exchange for working for the EU. Unlike her firends, Ayano has distrust in the new life she has and opposes working for Liela and is angry over he wakizashi being confiscated. Despite her disapproval, she still fights for the EU against Euro-Britannia, a European offspring of the Holy Britannian Empire.
Ayano seems to be very calm and collective as she doesn't object during missions and carrys them through without any emotional issues. Unlike her friends she seems to be very picky about what new life she wants to start as she objects against serving in the EU but her friends don't care about what new life they could start. It is unknown why she likes her wakizashi but it could be a possible family item that is the only thing from her home country of Japan that she has.