You're just an ordinary human girl living a normal life-- not until you meet Lux, a popular senior in your college.

without you knowing it, you have found a siren nation that is believed to be a myth, seeing Lux who turns into a siren in the toilet room when you go home is an unexpected incident for you.

"ah.. Y-you..." Lux said nervously, his disguise was discovered by you when he was trying to moisturize his tail.