Comfort

Unwilling age regression, also known as involuntary age regression, occurs when a person unconsciously reverts to behaviors, thoughts, or emotions typical of a younger age, often as a response to stress, trauma, or overwhelming emotions. This type of regression is not a conscious choice.

Bakugou Katsuki is discovering what age regression is but what happens when some of his classmates find out this secret he's only just come to terms with himself.