Masuku and fellow playmaker Reinhardt Fortuin have both extended their stay in Bloemfontein, along with centres David Brits and Evardi Boshoff, fullback Cohen Jasper, wing Daniel Kasende and scrumhalf Brenden de Kock.
The Cheetahs also secured the services of locks Mzwanele Zito and Siba Qoma from November, while wing Munier Hartzenberg will join from Griquas, and utility back Siba Xhamlashe has signed from Western Province.