An adult child, abbreviated AC, is an adult who takes on the role of a child in roleplay (ageplay). The scenario is related to that of an adult baby, but the difference is that the role is that of a child and not of an infant. The play age can be from toddler to puberty and mid-teenage — i.e. the AC may be in preschool, kindergarten or school age.
AC are frequently referred to as "Little girls" or "Little boys" (Littles collectively). The AC may choose to roleplay as their own gender or as another. Men who play the role of a Little girl, or the role of a Little boy who is subjected to forced cross-dressing as a girl (petticoat punishment) are sometimes referred to as "sissies". AC who play the role of schoolboys or schoolgirls are sometimes referred to as "schoolies".
If the play age is that of a schoolchild, school scenes can be played; if it is younger they are more limited to domestic scenes. But there is room for domestic playtime for any AC; for example: mealtime, bathtime, bedtime etc. scenes.
The play partner can play the role of the guardian such as a parent (typically referred to as "Daddy" or "Mommy"), uncle/aunt, nanny, doctor/nurse, babysitter, teacher, headmaster, tutor, governess, etc. The AC may misbehave and need punishment, allowing for a wide range of possible punitive measures; typically much wider than their Adult Baby counterparts. Spanking is among the all-time favourites, but there are dozens of other types of punishment, corporal and non-corporal, to add practically unlimited variety to the roleplay.
Other adult/child ageplay activities valued for their semi-punitive and embarrassing/humiliating and power exchange qualities include examinations, scrubbing, rectal temperature taking, the giving of enemas, or the wearing of diapers or training pants (frequently as punishment for bathroom related or unrelated misbehavior). This last example could be seen as unrealistic to the roll of a post-toddlerhood child, but it is nonetheless very common in AC scenes. This might be in part because many ACs are also sometimes adult babies (ABs); because diapers are very often a central part of AB scenes, those who take on both rolls might come to find them helpful as a surefire way to feel young. It might also be because many fetishists (diaper lovers) find wearing and using diapers physically pleasurable. Finally, it may be that what some ACs like about age play is not just the state of feigned childhood itself, but the fact that they have (or have been) regressed to that state. In this case, the experience of feeling like a child who was being treated as an infant or a toddler might be more intense or more enjoyable than simply pretending to be a certain age.
The AC may dress in childlike clothing (in adult size but childlike design) for a more realistic feeling, such as for Little boys:
- boy's T-shirts
- boy's school uniforms
- childlike briefs
- childlike nightwear, e.g. boy's pajamas
and for Little girls:
- dresses, often short
- skirts, often short, often pleated
- girls T-shirts
- childlike panties
- girl's school uniforms
- childlike nightwear, e.g. girl's pajamas or nightgowns
"Adult" items such as jewellery or watches may be removed, or replaced by corresponding children's style items. Little girls may also remove any make-up, lipstick, nail polish, etc., and may put on a girl-like hairstyle such as pigtails or braids.
AC and their guardian play partners may enter a long-term relationship, similar in some way to a Master/slave relationship but with different connotations. These relationships can be considered a subtype of domination and submission relationships and are typically referred to by the player's roles, such as:
- Stills from an F/F spanking video by Hand-Spanking.com in which the spankee plays the role of a kindergartener: ,