To be blunt, she's an absolute amateur girl. Moreover, it's a documentary. So there's no 'staged' eroticism. However, here we have the raw, genuine eros of an ordinary girl, who is nervous when the camera is turned on her, gradually opening up and feeling. Chiaki-chan, a naive girl who, despite being caressed and feeling good, is too embarrassed to make a sound, is suddenly shown a penis, bewildered, and covers her mouth. Her genuine reactions bring back the true excitement that had been almost forgotten!