  First, we study the fit of the Higgs boson rates, based on all the latest
collider data, in the effective framework for any Extra-Fermion(s) [EF]. The
best-fit results are presented in a generic formalism allowing to apply those
for the test of any EF scenario. The variations of the fit with each one of the
five fundamental parameters are described, and, the obtained fits can be better
than in the Standard Model (SM). We show how the determination of the EF
loop-contributions to the Higgs couplings with photons and gluons is relying on
the knowledge of the top and bottom Yukawa couplings (affected by EF mixings);
for determining the latter coupling, the relevance of the investigation of the
Higgs production in association with bottom quarks is emphasized. In the
instructive approximation of a single EF, we find that the constraints from the
fit already turn out to be quite predictive, in both cases of an EF mixed or
not with SM fermions, and especially when combined with the extra-quark
(-lepton) mass bounds from direct EF searches at the LHC (LEP) collider. In the
case of an unmixed extra-quark, non-trivial fit constraints are pointed out on
the Yukawa couplings for masses up to ~200 TeV. In particular, we define the
extra-dysfermiophilia, which is predicted at 68.27% C.L. for any single
extra-quark (independently of its electric charge). Another result is that,
among any components of SM multiplet extensions, the extra-quark with a -7/3
electric charge is the one preferred by the present Higgs fit.
