The House of Magical Doors. The Monsters Are Coming!

It has hundreds of doors that should not be opened, or else something terrifying will invade this world...
The Butler Demon, the cheerful fox Toi, the fairy Mellow, and the she-wolf Rёmi were having dinner peacefully when gigantic millipedes poured in through an open door. What to do?
Of course, flee! But that won't help - adventures will catch up with them anyway: horrifying monsters, a mad scientist, and even... a suspicious grandmother.
Watch out, the doors are opening...