One day, my mother-in-law came to Tokyo while I was living with my wife. Apparently, she had been scouted as an underwear model, so she persuaded her father-in-law to come and audition. Audition is in a week. During a rehearsal, I saw my girlfriend's mother-in-law wearing flashy underwear that secretly provoked men, and I couldn't help but feel the bulge in my crotch. Then, my girlfriend's mother-in-law noticed me and asked me to do a test shoot wearing her exciting underwear...