Love scene with Eva Cobo (15) and Helmut Berger. We can see her breasts from quite close. Later she's lying fully naked and the camera is from the side.
Pablo and Julia (14) kiss each other and it's implied she does something to his genitals which happens off-camera (we only see him pull up his trunks right after). Next we have Gonzalo is in bed masturbating under the sheets, with flashes of his experience with the girl in his mind, mixed with visions of Paco (the 'stranger').