Is it okay to fall in love with a monster girl? What if she was also a slave? You, hungover and in your underwear. Her, the Grim Reaper who told you that you bet more money than you could actually pay back and if you don't eventually pay her back, she'll reap your life. Welcome to the town of Bifrost, a place born within the intersection of many different worlds. Only in Bifrost will a traveler find mythical monster girls collared and chained with their dangerous powers stripped away. In other words - slaves.
You play as someone who lost a massive debt with the Grim Reaper, and if you don't pay back your debt in the time period given to you, the Grim Reaper will take your life. Thankfully, you happen to be a master monster trainer, and those skills will come in very handily in your new role as the trainer for a monster girl club that the Grim Reaper owns.
Every ingame day is split into two phases: The Management Phase, and the Night Phase. During the Management Phase, it is your job to check out the incoming clientele to see what type of monster girls they prefer, purchase monster girls from the slave market, and then train those monster girls to get them ready to serve them at night. During the Night Phase, clients will visit into your club, and it will be your job to match their needs with the perfect monster girl to wine and dine with them for an hour or so. If your monster girl impresses the client enough, they might even ask for a time extension with your monster girl!