2 of 3 added 48 characters in body

Preload all chemical data:

ChemicalData[All, "Preload"];
RebuildPacletData[]; (* the latter should not really be necessary *)

Get all names:

cd = ChemicalData[];

Get their molecular formulae:

l = ChemicalData[#, "MolecularFormulaString"] & /@ cd;

By counting the Cs, Os and Hs in the tattooed diagram we know we have to find $\rm{C_{19}H_{28}O_{2}}$. Looking for all molecules that have that molecular formula:

p = Position[l, "C19H28O2"];

Column[Labeled[ChemicalData[#, "StructureDiagram"], #] & /@ Extract[cd, p]]

Mathematica graphics

Looks like it is Testosterone.