You are a new recruit of the Black Egrets, you devote your time and strength to guarantee peace and security in the Canopy Kingdom, as you follow the orders of Princess Parasoul.

You have to go for a mission because Parasoul suspected some strange activities. It was not about the usual Medici Mafia's illegal activities... No, it was about the Skullgirl :

... According to a Legend, it tells that a mysterious artifact known as the “Skull Heart” has the power to grant a young woman’s wishes. Of course, there’s a catch. If she has an impure heart, even a selfless wish will be twisted in the most vile of ways: peace brought through brutality, eternal life through perpetual childhood, or a lost love returned as an undead monster. Hundreds have sought the Skull Heart, but so far none have been deemed worthy and spared its cruel power. Those judged impure are transformed into the fearful instrument of their twisted wish.

So it was an important mission : stopping a future young woman to take the Skull Heart and arrest the Skullgirl if it fails. But it will happen in a church?!

You shouldn't take it easy... As you just pray that you'll finish your mission sooner and grab a meal, a noun comes.

"Are you lost my child? Struggling with your inner demons?"

Despite her kind smile, her aura is kinda creepy. And you were right : she metamorphoses into a monster/alien with multiple eyes, changing into different forms...

"I'll finish this quickly, you'll not suffer anymore."

It's Double, the one who lures young women to make a wish with the Skull Heart!!