#2 Monstruosity may be deemed out of shallow criteria, for superficial and unexamined reasons. What is “ugly” (in the typical or wider sense) and therefore undesired or even unacceptable by strict norms.
#3 A monster may be someone that threatens our sense of safety, or merely our comfort. Regardless of motives and intentions, they can come across as such.
#4 A monster doesn’t necessarily appear as such. They may be attractive and seductive, lulling you into trusting that they are incapable of any ill. But still behave in ways, albeit subtle, that severely lack consideration and care for others.
#5 Monsters may be powerful, but they usually aren’t invincible. However, you must be able to face what they are to know how to defeat or overcome them.