In April 2005, José Vázquez (Suayo; Guitar and Vocals), Raúl Tola (Tol; Bass and Vocals) and Paco García (Kapo; Drums) formed Lisdexia. After giving a single concert under that name, Víctor Martínez (Susurros; Guitar and Vocals) joins the band and they change the name to SUJETO K.

In September of the same year they record their first demo and start playing gigs in the Valencian area. After selling out a first edition of 500 units, they re-released the demo with which they became known in the Levantine scene.