Yuna (pseudonym) is an office lady working in the sales department of a medical equipment manufacturer. A stunning beauty who looks great in black pantyhose, she boasts model-quality beautiful legs. She takes on a piston challenge using a fixed dildo for a high cash prize of 1 million yen. Though she normally gives off a cool impression, once the dildo is inserted, she suddenly becomes highly sensitive, gushing abundant pussy juice as she cums repeatedly. "So good... so good... haa..."—she becomes so lost in pleasure that she forgets all about the prize money, completely overwhelmed by orgasm after orgasm. She even achieves a record of 11 vaginal orgasms. Yet she realizes nothing beats a real cock, and an even thicker, ultra-fat real dick is inserted instead. Her pussy, already loosened and hypersensitive from the dildo, explodes with climax after climax from the bare cock, ultimately culminating in a creampie. Though she insisted she had to finish in five minutes due to work, it's unclear whether this affected her clients—but her passion and sincerity shine through in this intense performance.