Simple, sweet, and to the point, nice art, and fun enough gameplay.
Oh, and it's a type of comedy.
Prologue (The villainess saves you)
You start as a generic bandit in a gang, immediately get wiped out alongside your friends by the passing by heroine(white haired witch), and are only saved thanks to the villain(black haired witch), she has a petty grudge on the heroine and wants to get back at her by using you to pull some pranks/help her gain money, it's fairly obvious she just intends to exploit you but... she did save your life by altering what you are and you now NEED to do this, to live so...
Main Game (You do her bidding, aka: messing with the heroine)
Either choose to play the honorable bandit out for revenge for his fallen comrades and get the heroine to like you or just a generic lustful bandit and get her to see you as just some annoying pest she can't seem to get rid of, either way you're going to be sexually harassing her as much as possible for the sake of staying alive/earning money.(It's just flavor text that changes nothing, since you're going to have to flee from the villainess at the end of the game anyway, the heroine's opinion doesn't matter don't worry about it)
Ending (she tries to betray you, but you manage to overpower her and flee after having some fun with her)
Finally, you've accumulated enough money(did I mention money was magic, and you're basically a magic sucking vampire now?) for the villain to be satisfied and as the petty villain that she is, this means trouble for you, can't "just" flee you wouldn't survive long without a good supply of magic, can't stay either she made you she can probably unmake you even without her magic, time for a revolution! followed by a strategic retreat!!!
Epilogue (You're now safely in hiding, and the villainess apologizes to the heroine/works for her since you left her without any money)
It's not safe for you to get caught/found since the villainess might have the means and probably does have the will to get rid of you, so you disappear leaving her without any money(aka: magic), and with only one person left to turn to she goes to the heroine for help, coming clean about what she'd done and apologizing.