  We investigate emergent holography of weakly coupled two-dimensional
hyperK\"ahler sigma model on cotangent bundle of (N-1)-dimensional complex
projective space at zero and finite temperature. The sigma model is motivated
by the spacetime conformal field theory dual to the near-horizon geometry of Q1
D1-brane bound to Q5 D5-brane wrapped on four-torus times circle, where N =
Q1*Q5. The sigma model admits nontrivial instanton for all N greater than or
equal to 2, which serves as a local probe of emergent holographic spacetime. We
define emergent geometry of the spacetime as that of instanton moduli space via
Hitchin's information metric. At zero temperature, we find that emergent
geometry is AdS3. At finite temperature, time-periodic instanton is mappable to
zero temperature instanton via conformal transformation. Utilizing the
transformation, we show that emergent geometry is precisely that of the
non-extremal, non-rotating BTZ black hole.
