Itsuki's withdrawal from all social interaction, likely the result of bullying.
Bullying is defined as the repeated and intentional harming and humiliation of others, particularly those who are smaller, weaker, younger, or otherwise more vulnerable than the bully. Bullying is distinguished from ordinary aggression by its deliberate targeting of those with less power.
Bullying can include both verbal and physical attacks, as well as threats of harm, other forms of intimidation, and deliberate exclusion from activities. Bullying appears to peak between the ages of 11 and 13 and then declines as children get older. Overt physical aggression, such as kicking, hitting, and shoving, is most common in younger children; relational aggression, such as spreading rumors and social exclusion, becomes more common as children mature.
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