What is the fictional universe that XXX appears in?
S.T.R.I.K.E.
Like its Marvel Universe counterpart, this version of S.T.R.I.K.E. is the British division of S.H.I.E.L.D. S.T.R.I.K.E. also has ties with S.H.I.E.L.D.'s sister organization in Europe, the European Defense Initiative.
Marvel Universe