[A New Sensation... Gut-Wrenching On-Screen NTR!] I began to suspect my girlfriend, so I asked a trusted junior colleague to set up a test, leaving them alone together to verify the truth. As I nervously spied on them, I was shaken by an unimaginable turn of events. Hinako gazed at my junior in a sultry manner and said, "I haven't done it with him lately... I'm feeling pent up," seducing him outright. I panicked and tried to stop it, but my junior gave in, and things quickly escalated. Stripped naked, receiving a blowjob, then fucked hard—I could do nothing but watch the hellish scene unfold, climaxing in despair. To think the girl I loved was just a slut... Trying to test her on a whim was the stupidest thing I've ever done.