It's Friday night and thanks to an unexpected change of plans due to your little sister Hotaru suddenly being invited to a sleepover, you're able to find the time to attend a big costume party you've been invited to. Throwing on your best clothes, donning a cheap mask you picked up, and coming up with a quickly made up alias to conceal your identity- you're ready to party!

You arrive at the venue and immediately you're sucked into the thrill of complete anonymity as you mingle and interact with the other masked party-goers. After a while you can't help but notice there's one particular girl there who stands out to you- the air of mystery surrounding her drawing you in like a moth to the flame.