effortless
voluntary
a beneplacito
a discretion
abandoned
ad arbitrium
ad lib
ad libitum
al piacere
arbitrary
at choice
at pleasure
at will
autonomous
deliberate
discretional
discretionary
elective
free
free will
go-go
gratuitous
immoderate
incontinent
independent
indulgent
intemperate
intentional
irrepressible
lax
licentious
loose
nonmandatory
nonrestrictive
offered
optional
out of control
out of hand
permissive
reinless
riotous
self-acting
self-active
self-determined
self-determining
spontaneous
unasked
unbesought
unbidden
unbridled
uncalled-for
unchecked
artless
befogged
conversable
dimensionless
fun-loving
heartfelt
motiveless
racy
scrying
susceptive
teleological
unaffected
unconstrained
unfailing
uninhibited
unpremeditated
unquenchable
unruffled
unshackled
unstrained
unstudied
warm-hearted