Aika is a salesperson for a company that makes T-back underwear. Her sales are always at the top of the company even though she only specializes in selling to men. And her secret is... letting customers "experience" the effectiveness of underwear right at home. Because it is sold to men, of course Aika is also a model. Change underwear right in front of the customer, let them see, smell, and touch her round, plump butt. Aika even let customers fuck her to "test" the sexiness, elasticity, and suppleness of her panties! No man can resist Aika's charm, the number of loyal customers is increasing, and sales are also increasing rapidly...