Kidult
Kidult is a suitcase word (education from English kid 'child' and adult 'adult') and mainly describes an adult who consciously cultivates behavior, hobbies or preferences for products that are childlike or associated with children .
For example, products from the Hello Kitty series that were originally produced for young girls are very popular with adult women .
Occasionally the word is also used in the opposite sense: for a child or a young person who takes on responsibility very early on or shows other behavior that is typical of an adult or that is attributed to adults.
Both meanings set as opposed to terms such as Peter Pan syndrome and child-woman is not necessarily disparaging or psychopathological represent votes, but the expression Kidult can be used in these contexts.